CN1707309A - A Self-Balanced Equivalent Beaming Method and Quantum Truly Random Code Generating Device - Google Patents
A Self-Balanced Equivalent Beaming Method and Quantum Truly Random Code Generating Device Download PDFInfo
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Abstract
The present invention is self-balancing equiratio light beam splitting method and device and single probe quantum true random code generator constituted therewith, and features the connection of clock circuit output to the single photon source input and the clock input of the data processing circuit, the connection of the single photon detector to data input of the data processing circuit, the connection of single photon source output to the self-balancing equiratio light beam splitter input, the connection of the self-balancing equiratio light beam splitter output to the single photon detector input, and the optical delay set in the reflecting or transmitting optical path after the splitter and regulated to form proper optical path difference between reflected light and the transmitted light. After reflection in the reflectors in the end of the reflecting optical path and the transmitting optical path, the light is returned along the same path and output via the other port of the splitter.
Description
Technical field:
The invention belongs to optics and private communication technology field, particularly self-balancing geometric beam-splitting method and optical device, quantum device and quantum true random code generation device.
Background technology:
Random number can be divided into two kinds of pseudo random number and true random numbers." contemporary cryptology " (Cryptologie Contemporaine according to the publication in 1992 of French Ma Sen publishing house, Masson, 1992.) introduce, pseudo random number is to utilize the random number of complicated algorithm or the incompatible generation of algorithm groups, but, always algorithm is clocklike, as long as know this rule, pseudo random number is foreseeable in principle, therefore also just is not random number truly.
True random number can get by the randomness conversion of measuring some physical quantity, and the randomness of this random number depends on the randomness of measured physics process, and its application in fields such as secret communications will be got well more than pseudo random number.The physical process that is used for producing true random number has usually: physical processes such as nuclear decay process, electrical noise, optical radiation." statistical mathematics association annual report (Tokyo) " (Ann.Inst.Stat.Math.Tokyo 8,119 (1956)) introduced a kind of method of utilizing the nuclear decay process to produce random number, because it must use the device of radioactive material, difficult management not only, the equipment complexity, the cost height, and use inconvenience, have danger.
In recent years, the quantum random code generating apparatus that utilizes quantum-mechanical ultimate principle to realize, not only safety but also principle are clear, easy to operate, are not subjected to the restriction of bandwidth again.A kind of like this device has been introduced by U.S.'s " scientific instrument comment " (Rev.Sci.Instr.Vol.71 (2000) 1675-1680), its principle is: allow single photon by 1: 1 beam splitter, according to quantum randomness principle, photon will select one of two possible paths to leave beam splitter at random; Detect the path that photon is selected respectively with two detectors, produce 0,1 real random code of forming according to detected photon Actual path triggering following circuit.This device is subjected to the influence of factors such as the quantum efficiency of the splitting ratio of beam splitter, two detectors and ageing properties be inconsistent.Because process technology limit, actual being difficult to accomplished the splitting ratio strictness of beam splitter 1: 1; The performance of detector also can not be in full accord, even can system be adjusted to equilibrium state by other means, but As time goes on, because the ageing properties of device is inconsistent, the pollution of light path etc. all can be caused the unbalance once more of system, thereby make that the ratio of 0 and 1 in the random code of device output is inhomogeneous, influence the quality of random number.
Summary of the invention:
The present invention proposes a kind of self-balancing geometric beam-splitting method and device, is used for guaranteeing automatically the strict ratio that satisfies 1: 1 of splitting ratio, and constructs a kind of single probe quantum true random code generating apparatus based on this, is used for producing the uniform random code of 0,1 ratio.
Self-balancing geometric beam-splitting method of the present invention is reflected light and transmitted light with the incident light beam splitting, it is characterized in that this reflected light and transmitted light are done the inequality time-delay and reflect the back respectively to return from former road.
Described reflection can be directly reflection or equivalence reflection; Described transmission can be direct transmission or equivalent transmission.
Self-balancing geometric beam-splitting device of the present invention is made up of beam splitter, optical time delay device and reflection unit, and incident light is from the input of any one port of beam splitter, after the beam splitting at two the port outgoing reflected light and the transmitted light of the other side of beam splitter; It is characterized in that: on the light path of described reflected light or transmitted light, place the optical time delay device, perhaps on the light path of described reflected light and transmitted light, place the optical time delay device simultaneously, regulating the optical time delay device makes this reflected light and transmitted light form optical path difference, return from former road after the reflection unit reflection through being placed on reflected light path and transmitted light path end, through another port output of described beam splitter incident light one example.
Described beam splitter can be the fiber optic splitter of 50: 50 (or claim 3dB) polarization irrelevants, or the beam splitter of 50: 50 (or title 3dB) polarization irrelevants being made up of discrete component; Incident light is polarized light or nonpolarized light; Described reflection unit comprises the interface of catoptron or faraday's catoptron or beam splitter and air, vacuum or in the plating reflection horizon, interface of beam splitter and air, vacuum;
Described beam splitter can also be polarization fiber beam splitter or the polarization beam apparatus be made up of discrete component; At this moment, incident light is nature polarized light, circularly polarized light or linearly polarized light; Described reflection unit comprises the interface of catoptron or faraday's catoptron or beam splitter and air, vacuum or in the plating reflection horizon, interface of beam splitter and air, vacuum; Wherein when incident light was linearly polarized light, the polarization direction of its polarization direction and polarization beam apparatus in angle of 45 degrees.
Quantum true random code generating apparatus of the present invention, the input of order photon source and the clock input of data processing circuit are distinguished in the output of clock circuit, the output of single-photon detector links to each other with the input of the data of data processing circuit, it is characterized in that: the output of described single-photon source connects the input of self-balancing geometric beam-splitting device, the input of the output order photon detector of self-balancing geometric beam-splitting device; Described self-balancing geometric beam-splitting device is by beam splitter, optical time delay device and reflection unit are formed: incident light is from arbitrary port input of beam splitter, after the beam splitting respectively from two the port outgoing reflected light and the transmitted light of the other side of beam splitter, on the light path of this reflected light or transmitted light, place the optical time delay device, perhaps on the light path of this reflected light and transmitted light, place the optical time delay device simultaneously, regulating the optical time delay device makes reflected light and transmitted light form optical path difference, return from former road after the reflection unit reflection through being placed on reflected light path and transmitted light path end, through another port output of described beam splitter incident light one side.
Compare with existing method, self-balancing geometric beam-splitting method of the present invention has been taked transmitted light and reflected light are done to reflect the measure of exporting through serial behind the beam splitter once more after the relative inequality time-delay respectively.If output is reflected light, then export light and pass through beam splitter twice altogether, be reflection for the first time, be transmission for the second time, the probability of output is (reflectivity * transmissivity); If output is transmitted light, then export light and also pass through beam splitter twice, be transmission for the first time, be reflection for the second time, the probability of output is (transmissivity * reflectivity).By above analysis as can be known, both output probabilities are equal fully, be the strict ratio that satisfies 1: 1 of splitting ratio, so just guaranteed strict satisfied 1: 1 ratio of splitting ratio of output pulse automatically, the problem that the splitting ratio that has overcome existing beam-splitting method changes with the change of beam splitter.
Compare with existing beam splitting arrangement, self-balancing geometric beam-splitting device of the present invention at the reflected light of outgoing after the incident light beam splitting or/and place the optical time delay device on the light path of transmitted light, regulating the optical time delay device makes reflected light and transmitted light form optical path difference, return from former road after the reflection unit reflection through being placed on reflected light path and transmitted light path end, thereby make in time separately and all pass through beam splitter twice through the reflected light of another port output of beam splitter incident light one side and transmitted light, wherein reflected light reflection back transmission earlier, transmitted light elder generation transmission back reflection, therefore both output probabilities are equal fully, it is the strict ratio that satisfies 1: 1 of splitting ratio, and be not subjected to component ageing, the influence of environmental pollution etc. and the various factors of time correlation has overcome existing apparatus owing to the splitting ratio that adopts direct beam-splitting method to cause can not the strict problem that satisfies 1: 1 ratio.
Quantum true random code generating apparatus of the present invention is compared with existing random code generating apparatus, it is the time to go up two-way light separately with the incident light beam splitting that apparatus of the present invention adopt above-mentioned self-balancing geometric beam-splitting device, utilize single-photon detector to survey respectively in these two time periods, produce random code 0 or 1 according to the result who surveys, then a time period does not have if there is detectable signal the previous time period, then export random code 0, the previous time period does not have if there is detectable signal a back time period, then exports random code 1.Because strict satisfied 1: 1 ratio of the splitting ratio of above-mentioned self-balancing geometric beam-splitting device output light, thereby 0 and 1 ratio also is 1: 1 a strict ratio in the random code that generates, and has overcome the inhomogeneous and time dependent problem of random code 0,1 ratio that existing apparatus produces.
Description of drawings:
Fig. 1 is the synoptic diagram of first embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 2 is the synoptic diagram of second embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 3 is the synoptic diagram of the 3rd embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 4 is the synoptic diagram of the 4th embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 5 is the synoptic diagram of the 5th embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 6 is the synoptic diagram of the 6th embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 7 is the synoptic diagram of the 7th embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 8 is the synoptic diagram of the 8th embodiment of self-balancing geometric beam-splitting device of the present invention;
Fig. 9 is the synoptic diagram of the 9th embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 10 is the synoptic diagram of the tenth embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 11 is the synoptic diagram of the 11 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 12 is the synoptic diagram of the 12 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 13 is the synoptic diagram of the 13 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 14 is the synoptic diagram of the 14 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 15 is the synoptic diagram of the 15 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 16 is the synoptic diagram of the 16 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 17 is the synoptic diagram of the 17 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 18 is the synoptic diagram of the 18 embodiment of self-balancing geometric beam-splitting device of the present invention;
Figure 19 is the synoptic diagram of self-balancing geometric beam-splitting device nineteen embodiment of the present invention;
Figure 20 is the synoptic diagram of the 20 embodiment of self-balancing geometric beam-splitting device of the present invention.
Figure 21 is singly the pop one's head in principle schematic of quantum true random code generating apparatus of the present invention.
Embodiment:
Specify the embodiment of technical solution of the present invention below in conjunction with accompanying drawing.
Embodiment 1: the self-balancing geometric beam-splitting device that fiber optic splitter and catoptron are formed
Adopt 50: 50 fiber optic splitters and the catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 1 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (1b) and the end (1c) of fiber optic splitter (1) are placed catoptron (2) and (3) respectively, and port (1c) is gone up and placed optical time delay device (4).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (1d) from port (1a) input of fiber optic splitter (1), also can export from port (1a) from port (1d) input of fiber optic splitter (1).The photon of input is reflected light and transmitted light according to reflectivity, the transmissivity determined by splitting ratio by beam splitting, and reflected light is propagated by port (1b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (1); Transmitted light is propagated by port (1c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (1).Port (1c) is gone up the optical time delay device of placing (4) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (1d) output separates in time.
If what port (1d) received is reflected light, then export light and pass through beam splitter twice altogether, be reflection for the first time, be transmission for the second time, the probability of output is (reflectivity * transmissivity); If what port (1d) received is transmitted light, then export light and also pass through beam splitter twice, be transmission for the first time, be reflection for the second time, the probability of output is (transmissivity * reflectivity).By above analysis as can be known, both output probabilities are equal fully, and promptly the strict ratio that satisfies 1: 1 of splitting ratio has so just realized self-balancing geometric beam-splitting.
Embodiment 2: the self-balancing geometric beam-splitting device that fiber optic splitter and faraday's catoptron are formed
Adopt 50: 50 fiber optic splitters and faraday's catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 2 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (1b) and the end (1c) of fiber optic splitter (1) are placed faraday's catoptron (7) and (8) respectively, and port (1c) is gone up and placed optical time delay device (4).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (1d) from port (1a) input of fiber optic splitter (1), also can export from port (1a) from port (1d) input of fiber optic splitter (1).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (1b), is returned by former road, faraday's catoptron (7) reflection back, once more by beam splitter (1); Transmitted light is propagated by port (1c), is returned by former road, faraday's catoptron (8) reflection back, once more by beam splitter (1).Port (1c) is gone up the optical time delay device of placing (4) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (1d) output separates in time.
Embodiment 3: the self-balancing geometric beam-splitting device that fiber optic splitter utilizes the fiber end face reflection to form
Adopt 50: 50 fiber optic splitters of polarization irrelevant in the present embodiment and utilize the fiber end face reflection to form the self-balancing geometric beam-splitting device, Fig. 3 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: the port (1c) of fiber optic splitter (1) is gone up and is placed optical time delay device (4).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (1d) from port (1a) input of fiber optic splitter (1), also can export from port (1a) from port (1d) input of fiber optic splitter (1).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (1b), is returned by former road, the fiber end face of port (1b) reflection back, once more by beam splitter (1); Transmitted light is propagated by port (1c), is returned by former road, the fiber end face of port (1c) reflection back, once more by beam splitter (1).Port (1c) is gone up the optical time delay device of placing (4) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (1d) output separates in time.
Embodiment 4: the self-balancing geometric beam-splitting device that fiber optic splitter utilizes fiber end face plating reflective layer reflects to form
Adopt 50: 50 fiber optic splitters of polarization irrelevant in the present embodiment and utilize fiber end face plating reflective layer reflects to form the self-balancing geometric beam-splitting device, Fig. 4 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (1b) and the fiber end face (1c) of fiber optic splitter (1) are coated with reflection horizon (5) and (6) respectively, and port (1c) is gone up and placed optical time delay device (4).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (1d) from port (1a) input of fiber optic splitter (1), also can export from port (1a) from port (1d) input of fiber optic splitter (1).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (1b), and former road, the floor that is reflected (5) reflection back is returned, once more by beam splitter (1); Transmitted light is propagated by port (1c), and former road, the floor that is reflected (6) reflection back is returned, once more by beam splitter (1).Port (1c) is gone up the optical time delay device of placing (4) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (1d) output separates in time.
Embodiment 5: the self-balancing geometric beam-splitting device that fiber optic splitter and catoptron are formed
Adopt 50: 50 fiber optic splitters and the catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 5 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (1b) and the end (1c) of fiber optic splitter (1) are placed catoptron (2) and (3) respectively, and port (1b) is gone up and placed optical time delay device (4).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (1d) from port (1a) input of fiber optic splitter (1), also can export from port (1a) from port (1d) input of fiber optic splitter (1).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (1b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (1); Transmitted light is propagated by port (1c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (1).Port (1b) is gone up the optical time delay device of placing (4) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (1d) output separates in time.
Embodiment 6: the self-balancing geometric beam-splitting device that fiber optic splitter and catoptron are formed
Adopt 50: 50 fiber optic splitters and the catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 6 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (1b) and the end (1c) of fiber optic splitter (1) are placed catoptron (2) and (3) respectively, port (1b) and (1c) on all place optical time delay device (4), but both amount of delay do not wait.
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (1d) from port (1a) input of fiber optic splitter (1), also can export from port (1a) from port (1d) input of fiber optic splitter (1).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (1b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (1); Transmitted light is propagated by port (1c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (1).Port (1b) and the inequality optical time delay device of (1c) upward placing make reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (1d) output separates in time.
Embodiment 7: the self-balancing geometric beam-splitting device that beam splitter and catoptron are formed
Adopt 50: 50 beam splitters and the catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 7 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (9b) and the end (9c) of beam splitter (9) are placed catoptron (2) and (3) respectively, and port (9c) is gone up and placed optical time delay device (10).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (9d) from port (9a) input of beam splitter (9), also can export from port (9a) from port (9d) input of beam splitter (9).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (9b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (9); Transmitted light is propagated by port (9c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (9).Port (9c) is gone up the optical time delay device of placing (10) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (9d) output separates in time.
Embodiment 8: the self-balancing geometric beam-splitting device that beam splitter and faraday's catoptron are formed
Adopt 50: 50 beam splitters and faraday's catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 8 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (9b) and the end (9c) of beam splitter (9) are placed faraday's catoptron (7) and (8) respectively, and port (9c) is gone up and placed optical time delay device (10).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (9d) from port (9a) input of beam splitter (9), also can export from port (9a) from port (9d) input of beam splitter (9).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (9b), is returned by former road, faraday's catoptron (7) reflection back, once more by beam splitter (9); Transmitted light is propagated by port (9c), is returned by former road, faraday's catoptron (8) reflection back, once more by beam splitter (9).Port (9c) is gone up the optical time delay device of placing (10) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (9d) output separates in time.
Embodiment 9: the self-balancing geometric beam-splitting device that beam splitter and catoptron are formed
Adopt 50: 50 beam splitters and the catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Fig. 9 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (9b) and the end (9c) of beam splitter (9) are placed catoptron (2) and (3) respectively, and port (9b) is gone up and placed optical time delay device (10).
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (9d) from port (9a) input of beam splitter (9), also can export from port (9a) from port (9d) input of beam splitter (9).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (9b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (9); Transmitted light is propagated by port (9c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (9).Port (9b) is gone up the optical time delay device of placing (10) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (9d) output separates in time.
Embodiment 10: the self-balancing geometric beam-splitting device that beam splitter and catoptron are formed
Adopt 50: 50 beam splitters and the catoptron of polarization irrelevant to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 10 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (9b) and the end (9c) of beam splitter (9) are placed catoptron (2) and (3) respectively, port (9b) and (9c) on all place optical time delay device (10), but both amount of delay do not wait.
When using this device, incident light can be a polarized light, also can be nonpolarized light.Incident light can be exported from port (9d) from port (9a) input of beam splitter (9), also can export from port (9a) from port (9d) input of beam splitter (9).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (9b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (9); Transmitted light is propagated by port (9c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (9).Port (9b) and the inequality optical time delay device of (9c) upward placing make reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (9d) output separates in time.
Embodiment 11: the self-balancing geometric beam-splitting device that polarization fiber beam splitter and catoptron are formed
Adopt polarization fiber beam splitter and catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 11 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (11b) and the end (11c) of polarization fiber beam splitter (11) are placed catoptron (2) and (3) respectively, and port (11c) is gone up and placed optical time delay device (12).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (11d) from port (11a) input of polarization fiber beam splitter (11), also can export from port (11a) from port (11d) input of polarization fiber beam splitter (11).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (11b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (11); Transmitted light is propagated by port (11c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (11).Port (11c) is gone up the optical time delay device of placing (12) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (11d) output separates in time.
Embodiment 12: the self-balancing geometric beam-splitting device that polarization fiber beam splitter and faraday's catoptron are formed
Adopt polarization fiber beam splitter and faraday's catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 12 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (11b) and the end (11c) of polarization fiber beam splitter (11) are placed faraday's catoptron (7) and (8) respectively, and port (11c) is gone up and placed optical time delay device (12).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (11d) from port (11a) input of polarization fiber beam splitter (11), also can export from port (11a) from port (11d) input of polarization fiber beam splitter (11).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (11b), is returned by former road, faraday's catoptron (7) reflection back, once more by beam splitter (11); Transmitted light is propagated by port (11c), is returned by former road, faraday's catoptron (8) reflection back, once more by beam splitter (11).Port (11c) is gone up the optical time delay device of placing (12) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (11d) output separates in time.
Embodiment 13: the self-balancing geometric beam-splitting device that the polarization fiber beam splitter utilizes the fiber end face reflection to form
Adopt the polarization fiber beam splitter in the present embodiment and utilize the fiber end face reflection to form the self-balancing geometric beam-splitting device, Figure 13 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: the port (11c) of polarization fiber beam splitter (11) is gone up and is placed optical time delay device (12).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (11d) from port (11a) input of polarization fiber beam splitter (11), also can export from port (11a) from port (11d) input of polarization fiber beam splitter (11).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (11b), is returned by former road, the fiber end face of port (11b) reflection back, once more by beam splitter (11); Transmitted light is propagated by port (11c), is returned by former road, the fiber end face of port (11c) reflection back, once more by beam splitter (11).Port (11c) is gone up the optical time delay device of placing (12) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (11d) output separates in time.
Embodiment 14: the self-balancing geometric beam-splitting device that the polarization fiber beam splitter utilizes fiber end face plating reflective layer reflects to form
Adopt the polarization fiber beam splitter in the present embodiment and utilize fiber end face plating reflective layer reflects to form the self-balancing geometric beam-splitting device, Figure 14 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: the port (11b) and the fiber end face (11c) of polarization fiber beam splitter (11) plate reflection horizon (5) and (6) respectively, and port (11c) is gone up and placed optical time delay device (12).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (11d) from port (11a) input of polarization fiber beam splitter (11), also can export from port (11a) from port (11d) input of polarization fiber beam splitter (11).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (11b), and former road, the floor that is reflected (5) reflection back is returned, once more by beam splitter (11); Transmitted light is propagated by port (11c), and former road, the floor that is reflected (6) reflection back is returned, once more by beam splitter (11).Port (11c) is gone up the optical time delay device of placing (12) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (11d) output separates in time.
Embodiment 15: the self-balancing geometric beam-splitting device that polarization fiber beam splitter and catoptron are formed
Adopt polarization fiber beam splitter and catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 15 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (11b) and the end (11c) of polarization fiber beam splitter (11) are placed catoptron (2) and (3) respectively, and port (11b) is gone up and placed optical time delay device (12).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (11d) from port (11a) input of polarization fiber beam splitter (11), also can export from port (11a) from port (11d) input of polarization fiber beam splitter (11).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (11b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (11); Transmitted light is propagated by port (11c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (11).Port (11b) is gone up the optical time delay device of placing (12) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (11d) output separates in time.
Embodiment 16: the self-balancing geometric beam-splitting device that polarization fiber beam splitter and catoptron are formed
Adopt polarization fiber beam splitter and catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 16 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (11b) and the end (11c) of polarization fiber beam splitter (11) are placed catoptron (2) and (3) respectively, port (11b) and (11c) on all place optical time delay device (12), but both amount of delay are unequal.
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (11d) from port (11a) input of polarization fiber beam splitter (11), also can export from port (11a) from port (11d) input of polarization fiber beam splitter (11).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (11b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (11); Transmitted light is propagated by port (11c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (11).Port (11b) and (11c) on inequality optical time delay device make reflected light and transmitted light have optical path difference, therefore reflected light and the transmitted light from port (11d) output separates in time.
Embodiment 17: the self-balancing geometric beam-splitting device that polarization beam apparatus and catoptron are formed
Adopt polarization beam apparatus and catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 17 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (13b) and the end (13c) of polarization beam apparatus (13) are placed catoptron (2) and (3) respectively, and port (13c) is gone up and placed optical time delay device (14).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (13d) from port (13a) input of polarization beam apparatus (13), also can export from port (13a) from port (13d) input of polarization beam apparatus (13).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (13b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (13); Transmitted light is propagated by port (13c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (13).Port (13c) is gone up the optical time delay device of placing (14) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (13d) output separates in time.
Embodiment 18: the self-balancing geometric beam-splitting device that polarization beam apparatus and faraday's catoptron are formed
Adopt polarization beam apparatus and faraday's catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 17 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (13b) and the end (13c) of polarization beam apparatus (13) are placed faraday's catoptron (7) and (8) respectively, and port (13c) is gone up and placed optical time delay device (14).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (13d) from port (13a) input of polarization beam apparatus (13), also can export from port (13a) from port (13d) input of polarization beam apparatus (13).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (13b), is returned by former road, faraday's catoptron (7) reflection back, once more by beam splitter (13); Transmitted light is propagated by port (13c), is returned by former road, faraday's catoptron (8) reflection back, once more by beam splitter (13).Port (13c) is gone up the optical time delay device of placing (14) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (13d) output separates in time.
Embodiment 19: the self-balancing geometric beam-splitting device that polarization beam apparatus and catoptron are formed
Adopt polarization beam apparatus and catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 19 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (13b) and the end (13c) of polarization beam apparatus (13) are placed catoptron (2) and (3) respectively, and port (13b) is gone up and placed optical time delay device (14).
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (13d) from port (13a) input of polarization beam apparatus (13), also can export from port (13a) from port (13d) input of polarization beam apparatus (13).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (13b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (13); Transmitted light is propagated by port (13c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (13).Port (13b) is gone up the optical time delay device of placing (14) makes reflected light and transmitted light have optical path difference, and therefore reflected light and the transmitted light from port (13d) output separates in time.
Embodiment 20: the self-balancing geometric beam-splitting device that polarization beam apparatus and catoptron are formed
Adopt polarization beam apparatus and catoptron to form the self-balancing geometric beam-splitting device in the present embodiment, Figure 20 has provided the self-balancing geometric beam-splitting schematic representation of apparatus of present embodiment: two ports (13b) and the end (13c) of polarization beam apparatus (13) are placed catoptron (2) and (3) respectively, port (13b) and (13c) on all place optical time delay device (14), but both amount of delay are unequal.
When using this device, incident light must be nature polarized light, circularly polarized light or linearly polarized light, wherein when incident is linearly polarized light, its polarization direction must with the polarization direction of polarization beam apparatus in angle of 45 degrees.Incident light can be exported from port (13d) from port (13a) input of polarization beam apparatus (13), also can export from port (13a) from port (13d) input of polarization beam apparatus (13).Incident light is reflected light and transmitted light by beam splitting, and reflected light is propagated by port (13b), and former road, the mirror that is reflected (2) reflection back is returned, once more by beam splitter (13); Transmitted light is propagated by port (13c), and former road, the mirror that is reflected (3) reflection back is returned, once more by beam splitter (13).Port (13b) and (13c) on inequality optical time delay device make reflected light and transmitted light have optical path difference, therefore reflected light and the transmitted light from port (13d) output separates in time.
Embodiment 21: the synoptic diagram of single probe quantum true random code generating apparatus
Present embodiment is a kind of quantum true random code generating apparatus of base configuration with the self-balancing geometric beam-splitting device, Figure 21 has provided the principle schematic of single probe quantum true random code generating apparatus of present embodiment: the clock input of the input of the output difference order photon source (16) of clock circuit (15) and data processing circuit (19), the output of single-photon source (16) connects the input of self-balancing geometric beam-splitting device (17), the input of the output order photon detector (18) of self-balancing geometric beam-splitting device (17), the output of single-photon detector (18) connect the data input of data processing circuit (19).Wherein self-balancing geometric beam-splitting device (17) can be any one among the foregoing description 1～embodiment 20.
When using this device, clock circuit (15) produces three tunnel clock signals, and wherein one tunnel clock control single-photon source (16) produces single photon, and the two-way clock connects the input end of clock of data processing circuit (19) in addition.The light of single-photon source (16) output is to go up two-way light separately the time to deliver to single-photon detector (18) and survey through self-balancing geometric beam-splitting device (17) beam splitting, data processing circuit (19) is monitored the output of photon detector (18), and determines output according to the clock signal that receives.If all there is detectable signal two time periods or does not all have detectable signal, then output is under an embargo; If only detectable signal is arranged, then allow output, according to prior agreement output random code 0 or 1 and produce clock signal a time period.In the present embodiment, if the previous time period have detectable signal then a time period do not have, then export 0, the previous time period does not have if there is detectable signal a back time period, then exports 1.Random code that data processing circuit (19) produces and clock signal are given computing machine (21) by ISA/PCI card (20) and are carried out subsequent treatment.
This device both can be encapsulated on the Computer I SA/PCI card of standard, also can be used as independent circuit module and used.
Claims (7)
1, a kind of self-balancing geometric beam-splitting method is reflected light and transmitted light with the incident light beam splitting, it is characterized in that this reflected light and transmitted light are done the inequality time-delay and reflect the back respectively to return from former road.
2, a kind of self-balancing geometric beam-splitting device is made up of beam splitter, optical time delay device and reflection unit, after the incident light beam splitting of the arbitrary port of beam splitter input at two the port outgoing reflected light and the transmitted light of the other side of beam splitter; It is characterized in that: at described reflected light or/and place the optical time delay device on the light path of transmitted light, regulating the optical time delay device makes this reflected light and transmitted light form optical path difference, return from former road after the reflection unit reflection through being placed on reflected light path and transmitted light path end, through another port output of described beam splitter incident light one side.
3, self-balancing geometric beam-splitting method as claimed in claim 1 or 2 or device are characterised in that described be reflected into direct reflection or equivalence reflection; Describedly be transmitted as direct transmission or equivalent transmission.
4, self-balancing geometric beam-splitting method as claimed in claim 1 or 2 or device are characterised in that described beam splitter is the fiber optic splitter of 50: 50 polarization irrelevants, or the beam splitter of 50: 50 polarization irrelevants being made up of discrete component; Incident light is polarized light or nonpolarized light; Described reflection unit comprises the interface of catoptron or faraday's catoptron or beam splitter and air, vacuum or in the plating reflection horizon, interface of beam splitter and air, vacuum.
5, self-balancing geometric beam-splitting method as claimed in claim 1 or 2 or device are characterised in that described beam splitter is polarization fiber beam splitter or the polarization beam apparatus be made up of discrete component; Incident light is nature polarized light, circularly polarized light or linearly polarized light; Described reflection unit comprises the interface of catoptron or faraday's catoptron or beam splitter and air, vacuum or in the plating reflection horizon, interface of beam splitter and air, vacuum.
6, self-balancing geometric beam-splitting method as claimed in claim 5 or device are characterised in that when incident light was linearly polarized light, the polarization direction of its polarization direction and polarization beam apparatus in angle of 45 degrees.
7, a kind of quantum true random code generating apparatus, the input of order photon source and the clock input of data processing circuit are distinguished in the output of clock circuit, the output of single-photon detector links to each other with the input of the data of data processing circuit, it is characterized in that: the output of described single-photon source connects the input of self-balancing geometric beam-splitting device, the input of the output order photon detector of self-balancing geometric beam-splitting device; Described self-balancing geometric beam-splitting device is made up of beam splitter, optical time delay device and reflection unit: after the incident light beam splitting of port input of beam splitter from the reflected light of two port outgoing of an other side or/and the light path of transmitted light is placed the optical time delay device, regulating the optical time delay device makes reflected light and transmitted light form optical path difference, return from former road after the reflection unit reflection through being placed on reflected light path and transmitted light path end, through another port output of described beam splitter incident light one side.
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| US6188768B1 (en) * | 1998-03-31 | 2001-02-13 | International Business Machines Corporation | Autocompensating quantum cryptographic key distribution system based on polarization splitting of light |
| US6522749B2 (en) * | 1999-01-21 | 2003-02-18 | Nec Laboratories America, Inc. | Quantum cryptographic communication channel based on quantum coherence |
| CN1558581A (en) * | 2004-01-19 | 2004-12-29 | 华东师范大学 | A True Random Source of Optical Quantum |
| CN1561018A (en) * | 2004-02-24 | 2005-01-05 | 华东师范大学 | Polarization-independent single-photon waveguide phase modulation device |
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| CN108563422B (en) * | 2018-04-17 | 2020-10-09 | 图灵人工智能研究院（南京）有限公司 | Random number generator and random number generating method |
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