CN116896416A - A device and method for preparing multi-channel broadband light-atom interface - Google Patents

Abstract

The invention relates to a device and method for preparing a multi-channel broadband optical-atom interface. The invention prepares a multi-channel broadband atomic frequency comb in an erbium-doped solid material by combining optical frequency comb generation technology and frequency chirp control technology. The multi-channel broadband atomic frequency comb performs time-domain multi-mode storage of one photon in the quantum correlation or entanglement photon pair of broadband multi-frequency multiplexing in the optical communication band, thereby establishing the quantum correlation or entanglement between the other photon and the atomic frequency comb. Formation of light-atom interface. Each component used in the present invention to prepare a multi-channel broadband light-atom interface can be derived from mature optoelectronic devices, which is conducive to the development of practical quantum network nodes based on light-atom interfaces. The optical-atom interface prepared by this method has the advantages of large bandwidth and multi-channel, and can be widely used in fields such as quantum communication and quantum entanglement networks.

Description

A device and method for preparing multi-channel broadband light-atom interface

Technical field

The invention belongs to the field of quantum information, and specifically relates to a multi-channel broadband optical communication band optical-atom interface preparation device and method.

Background technique

A quantum network consists of local quantum nodes and quantum channels connecting local quantum nodes. The function of local quantum nodes is to acquire, process and transmit quantum information, while the function of quantum channels is to realize the connection of local quantum nodes. This connection can effectively realize information exchange between local quantum nodes and improve information processing capabilities. Therefore, how to build an efficient and practical quantum channel is the key to building a quantum network. As a common carrier of quantum information, photon transmission in any transmission medium has the problem of signal attenuation as the distance increases, which limits its propagation distance. To address this problem, an effective solution is to use the quantum relay method to realize the entanglement exchange of qubits between different nodes, and then establish full-link entanglement to realize the interconnection of quantum nodes at any distance. A complete quantum relay node needs to include basic components such as quantum memory and Bell state measurement device. Quantum memory plays a vital synchronization role in the entanglement exchange process.

As an important device for realizing quantum networks, the physical basis for realizing quantum memory is to utilize the interaction between light and atoms. Atoms establish photoatom interfaces by absorbing photons, which realizes the storage of light quantum states. An important consideration for quantum memory performance is storage bandwidth, and wider-bandwidth memory is necessary to increase network communication speeds. Currently, commonly used physical systems used to establish optical atom interfaces include: single atoms, atomic ensembles, rare earth-doped solid-state ensembles, NV/SiV color centers, quantum dots, optomechanical oscillators, etc. However, the currently implemented optical atom interface has problems such as a small number of channels and low storage bandwidth, which limits the communication speed of quantum networks. Therefore, there is an urgent need to develop a multi-channel, large-bandwidth light-atom interface preparation device.

Contents of the invention

The technical problem to be solved by the present invention is to provide a multi-channel broadband optical communication band light-atom interface implementation method in response to the existing needs of the existing technology.

In order to solve the above technical problems, embodiments of the present invention provide a multi-channel broadband optical communication band optical-atom interface preparation device, including a multi-channel broadband atomic frequency comb preparation device and a multi-frequency mode multiplexed optical communication band quantum correlation source or quantum Entanglement source, the two are connected through optical fiber;

The multi-channel broadband atomic frequency comb preparation device uses optical frequency comb generation technology and frequency chirp control technology to prepare multi-channel broadband atomic frequency combs in erbium-doped solid materials;

The multi-frequency mode multiplexed optical communication band quantum correlation source or quantum entanglement source generates multi-frequency mode multiplexed quantum correlation photon pairs or quantum entangled photon pairs through periodically polarized lithium niobate waveguides, and the atomic frequency comb pairs One photon in the quantum correlated photon pair or the quantum entangled photon pair is stored in a time domain multi-mode, and a quantum correlation between the other photon in the quantum correlated photon pair or the quantum entangled photon pair and the atomic frequency comb is established, or Quantum entanglement forms a multi-channel bandwidth optical communication band light-atom interface.

On the basis of the above technical solution, the present invention can also make the following improvements.

Further, the multi-channel broadband atomic frequency comb preparation device includes a first laser source 15, a first optical intensity modulator 16, a first optical phase modulator 17, a second optical phase modulator 18, and an optical switch 19 connected in sequence. and a first adjustable light attenuator 20, one end of the first adjustable light attenuator 20 is connected to the optical switch 19, and the other end of the first adjustable light attenuator 20 is connected to the first port of the optical circulator 21 , the second port of the optical circulator 21 is connected to one end of the erbium-doped solid material 22;

The first laser source 15 is used to provide continuous and stable pump light;

The light intensity modulator 16 and the first optical phase modulator 17 are used to modulate the pump light output by the first laser source 15 into an optical frequency comb with several comb teeth;

The second optical phase modulator 18 is used to load the optical frequency comb with periodic frequency shifting signals. In each cycle, the comb teeth will be frequency shifted several times at equal intervals. The interval after each comb tooth undergoes periodic frequency shifting. It is a frequency domain mode, and an optical frequency comb with several comb-like teeth becomes a multi-mode pump light;

The first adjustable optical attenuator 20 is used to adjust the power of pump light.

Further, the multi-frequency mode multiplexed quantum correlation source or quantum entanglement source includes a second laser source 1, a second light intensity modulator 2, an optical amplifier 3, a second adjustable optical attenuator 4, and a polarization control unit connected in sequence. 5, polarizer 6, nonlinear crystal waveguide 7, first optical isolator 8;

One end of the first optical isolator 8 is connected to the nonlinear crystal waveguide 7 , and the other end of the first optical isolator 8 is connected to the common end (C end) of the first dense wavelength division multiplexer 9 . The transmission end (T end) of the wavelength division multiplexer 9 is connected to one end of the first optical filter 10, and the reflection end (R end) of the first dense wavelength division multiplexer 9 is connected to the second dense wavelength division multiplexer 9. The common end (C end) of 11 is connected, the transmission end (T end) of the second dense wavelength division multiplexer 11 is connected with the input end of the second optical filter 12, and the N outputs of the second optical filter 12 terminals are respectively connected to the N transmission terminals (T terminals) of the third dense wavelength division multiplexer 13, and the common terminal (C terminal) of the third dense wavelength division multiplexer 13 is connected to one terminal of the second optical isolator 14. The other end of the second optical isolator 14 is connected to one end of the erbium-doped solid material 22 in the multi-channel broadband atomic frequency comb preparation device.

Further, the erbium-doped solid material 22 is an erbium-doped lithium niobate crystal, an erbium-doped yttrium silicate crystal, an erbium-doped quartz fiber, or an erbium-doped gadolinium vanadate crystal.

Further, the first laser source 15 and the second laser source 1 are solid-state laser sources, gas laser sources, semiconductor laser sources or dye laser sources.

Further, the first intensity modulator 16 and the second intensity modulator 2 are intensity modulators based on the acousto-optic effect or the electro-optic effect;

And/or, the first optical phase modulator 17 and the second optical phase modulator 18 are electro-optical phase modulators using KDP crystal or lithium niobate crystal as the electro-optical crystal.

Further, the first dense wavelength division multiplexer 9, the second dense wavelength division multiplexer 11 and the third dense wavelength division multiplexer 13 are thin film type dense wavelength division multiplexers and volume grating type dense wavelength division multiplexers. device, arrayed waveguide grating type dense wavelength division multiplexer or fiber grating type dense wavelength division multiplexer.

Further, the first optical filter 10 and the second optical filter 12 are fiber Bragg grating filters, cascaded fiber Bragg grating filters or volume grating filters;

And/or, the polarization controller 5 is a wave plate polarization controller or an optical fiber polarization controller.

In order to solve the above technical problems, embodiments of the present invention provide a method for preparing a multi-channel broadband optical communication band light-atom interface, which is implemented by using the above-mentioned multi-channel broadband optical communication band light-atom interface preparation device, including the following steps:

Use optical frequency comb generation technology and frequency chirp control technology to prepare multi-channel broadband atomic frequency combs in erbium-doped solid materials;

The atomic frequency comb performs time-domain multi-mode storage of one photon in a quantum correlated photon pair or a quantum entangled photon pair in the optical communication band multiplexed in a broadband multi-frequency mode, and establishes the quantum correlated photon pair or quantum entangled photon pair. The quantum correlation or quantum entanglement between another photon and the atomic frequency comb forms a multi-channel broadband optical communication band light-atom interface.

Further, the preparation method of the atomic frequency comb specifically includes the following steps:

The optical frequency comb technology is used to generate an optical frequency comb with several comb teeth. The frequency chirp control technology is used to cause the optical frequency comb to generate periodic frequency shifts. In each cycle, the comb teeth are frequency shifted several times at equal intervals. Each comb tooth The interval after periodic frequency shifting is a frequency domain mode. An optical frequency comb with several comb-like teeth becomes a multi-mode pump light. The multi-mode pump light pumps the erbium-doped solid-state material. The pump light and doped solid-state material The erbium ion ensemble in the erbium solid material interacts, and the spectral hole burning principle is used to excite the corresponding erbium ions in the erbium-doped solid material, and the remaining ground state erbium ions form a multi-channel atomic frequency comb.

The beneficial effects of the present invention are: the present invention relates to a multi-channel broadband optical communication band optical-atom interface preparation device, which uses optical frequency comb technology to produce an optical frequency comb with several comb teeth, and uses frequency chirp control technology to make the optical frequency comb The comb teeth of the comb produce periodic frequency shifts, and the comb teeth are frequency shifted several times in each cycle, and the frequency shift amount of the frequency shifts is one to several times a set value. Any comb tooth that undergoes periodic frequency shifting represents a frequency domain mode, and an optical frequency comb with several comb teeth becomes a multi-mode pump light. The multi-mode pump light generated after the above modulation is input into the erbium-doped solid material. The pump light interacts with the erbium ion ensemble in the erbium-doped solid material. The spectral hole burning principle is used to prepare the erbium-doped solid material. Output multi-channel atomic frequency comb. Because erbium ions have a broad absorption spectrum, atomic frequency combs can be prepared over a wide range. The atomic frequency comb interacts with idler frequency photons to achieve storage, establish quantum correlation/entanglement between different frequency mode signal photons and erbium ion ensembles, and form a light-atom interface.

Each component of the light-atom interface prepared by the present invention in the optical communication band can be derived from mature optoelectronic devices, which is conducive to the practical development of quantum nodes based on the light-atom interface. The light-atom interface prepared by this method has the advantages of easy implementation, large bandwidth, and multi-channel. The prepared rare earth quantum memory can achieve large bandwidth, multi-channel storage of entangled photons in the optical communication band, and improve the transmission speed of quantum information. It can produce beneficial effects and can be widely used in fields such as quantum communications and quantum entanglement networks.

Description of the drawings

Figure 1 is a schematic structural diagram of a multi-channel broadband optical communication band optical-atom interface preparation device according to an embodiment of the present invention;

Figure 2 shows the absorption spectra of five channels of atomic frequency combs in the erbium-doped solid material 22 obtained by using a multi-channel broadband optical communication band optical-atom interface preparation device according to an embodiment of the present invention.

In the drawings, the parts represented by each number are listed as follows:

1. Second laser source, 2. Second light intensity modulator, 3. Optical amplifier, 4. Second adjustable optical attenuator, 5. Polarization controller, 6. Polarizer, 7. Nonlinear crystal waveguide, 8. The first optical isolator, 9. The first dense wavelength division multiplexer, 10. The first optical filter, 11. The second dense wavelength division multiplexer, 12. The second optical filter, 13. The third Dense wavelength division multiplexer, 14. Second optical isolator, 15. First laser source, 16. First optical intensity modulator, 17. First optical phase modulator, 18. Second optical phase modulator, 19 , Optical switch, 20. First adjustable optical attenuator, 21. Optical circulator, 22. Erbium-doped solid material.

Detailed ways

The principles and features of the present invention are described below with reference to the accompanying drawings. The examples cited are only used to explain the present invention and are not intended to limit the scope of the present invention.

As shown in Figure 1, the first embodiment of the present invention provides a multi-channel broadband optical communication band optical-atom interface preparation device, including a multi-channel broadband atomic frequency comb preparation device and a multi-frequency mode multiplexed optical communication band quantum correlation source or quantum entanglement source, the two are connected through optical fibers;

The multi-channel broadband atomic frequency comb preparation device uses optical frequency comb generation technology and frequency chirp control technology to prepare multi-channel broadband atomic frequency combs in erbium-doped solid materials;

The multi-frequency mode multiplexed optical communication band quantum correlation source or quantum entanglement source generates multi-frequency mode multiplexed quantum correlation photon pairs or quantum entangled photon pairs through periodically polarized lithium niobate waveguides, and the atomic frequency comb pairs One photon in the quantum correlated photon pair or the quantum entangled photon pair is stored in a time domain multi-mode, and a quantum correlation between the other photon in the quantum correlated photon pair or the quantum entangled photon pair and the atomic frequency comb is established, or Quantum entanglement forms a multi-channel bandwidth optical communication band light-atom interface.

The above embodiment combines optical frequency comb and frequency chirp control technology to simultaneously prepare multiple large-bandwidth atomic frequency combs in an erbium-doped solid-state material, and cooperates with multi-frequency mode multiplexing associated/entangled photon storage to achieve multi-channel light-atom interface.

In this embodiment, the multi-channel broadband atomic frequency comb preparation device includes a first laser source 15, a first optical intensity modulator 16, a first optical phase modulator 17, a second optical phase modulator 18, and an optical Turn on the light 19 and the first adjustable light attenuator 20. One end of the first adjustable light attenuator 20 is connected to the optical switch 19, and the other end of the first adjustable light attenuator 20 is connected to the first end of the optical circulator 21. The ports are connected, and the second port of the optical circulator 21 is connected to one end of the erbium-doped solid material 22;

The first laser source 15 is used to provide continuous and stable pump light;

The light intensity modulator 16 and the first optical phase modulator 17 are used to modulate the pump light output by the first laser source 15 into an optical frequency comb with several comb teeth;

The second optical phase modulator 18 is used to load the optical frequency comb with periodic frequency shifting signals. In each cycle, the comb teeth will be frequency shifted several times at equal intervals. The interval after each comb tooth undergoes periodic frequency shifting. It is a frequency domain mode, and an optical frequency comb with several comb-like teeth becomes a multi-mode pump light;

The first adjustable optical attenuator 20 is used to adjust the power of pump light.

The multi-frequency mode multiplexing quantum correlation source or quantum entanglement source includes a second laser source 1, a second light intensity modulator 2, an optical amplifier 3, a second adjustable light attenuator 4, a polarization controller 5, which are connected in sequence. Polarizer 6, nonlinear crystal waveguide 7, first optical isolator 8;

One end of the first optical isolator 8 is connected to the nonlinear crystal waveguide 7 , and the other end of the first optical isolator 8 is connected to the common end (C end) of the first dense wavelength division multiplexer 9 . The transmission end (T end) of the wavelength division multiplexer 9 is connected to one end of the first optical filter 10, and the reflection end (R end) of the first dense wavelength division multiplexer 9 is connected to the second dense wavelength division multiplexer 9. The common end (C end) of 11 is connected, the transmission end (T end) of the second dense wavelength division multiplexer 11 is connected with the input end of the second optical filter 12, and the N outputs of the second optical filter 12 terminals are respectively connected to the N transmission terminals (T terminals) of the third dense wavelength division multiplexer 13, and the common terminal (C terminal) of the third dense wavelength division multiplexer 13 is connected to one terminal of the second optical isolator 14. The other end of the second optical isolator 14 is connected to one end of the erbium-doped solid material 22 in the multi-channel broadband atomic frequency comb preparation device.

Among them, the first laser source 15 outputs narrow linewidth continuous pump light with a central wavelength of 1531.88 nm, and the first laser source 15 adopts an external cavity semiconductor laser;

The narrow linewidth continuous pump light output by the first laser source 15 is input into the first light intensity modulator 16 and is intensity modulated into pulsed light. The first light intensity modulator 16 uses a lithium niobate electro-optical intensity modulator;

The pulsed light output by the first optical intensity modulator 16 is input to the first optical phase modulator 17. The first optical phase modulator converts the input pulsed light into a central wavelength at 1531.88nm, comb tooth spacing is 15GHz, and the number of comb teeth is 5 optical frequency combs;

The optical frequency comb output by the first optical phase modulator 17 is input to the second optical phase modulator 18. According to the principle of electro-optical phase modulation, the frequency sweep range of the second optical phase modulator 18 is loaded to be 0-5GHz, and the frequency sweep interval is 50MHz. , a swept microwave signal with a frequency sweep period of 10 microseconds, and the optical frequency comb input into it is periodically shifted. In each period, the optical frequency comb range is realized from -5GHz to 5GHz, with an interval of 50MHz; the first optical phase The modulator 17 and the second optical phase modulator 18 adopt lithium niobate electro-optical phase modulators.

The optical switch 19 adopts a 1×2 MEMS fiber optical switch, which is used to control the on and off of the pump light for preparing the atomic frequency comb, and remains "on" before the multiplexed idler photons enter the erbium-doped solid material 22. The idler photons Entering the erbium-doped solid state material 22 remains "off". In this embodiment, the optical frequency comb output by the second optical phase modulator 18 is input into the optical switch 19, and the optical switch operates in the "on" or "off" state according to the electrical signal loaded thereon. In the "on" state, the optical frequency comb input to the optical switch 19 is output from its output end; in the "off" state, the optical frequency comb input to the optical switch 19 is not output from its output end. In a 1s period, the light switch remains "on" for 300ms and remains "off" for the rest of the time.

The second intensity modulator 2 modulates the narrow linewidth continuous laser output by the second laser source 1 into pulsed pump light; in this embodiment, the second laser source 1 outputs continuous pump light with a central wavelength of 1540.60nm. Laser; the continuous pump laser output by the second laser source 1 is input to the second light intensity modulator 2, and the second intensity modulator 2 modulates the continuous pump laser into a pulse pump laser with a pulse width of 300ps; the second laser source 1 An external cavity semiconductor laser is used, and the second intensity modulator 2 is a lithium niobate electro-optical intensity modulator.

The optical amplifier 3 and the second adjustable optical attenuator 4 realize the adjustment of the pump optical power; in this embodiment, the pulse pump laser output by the second intensity modulator 2 is input to the second optical amplifier 3, and the second optical amplifier 3. Realize the power amplification of the pulse pump laser input into it;

The pulse pump laser output from the second optical amplifier 3 is input into the second optical attenuator 4 to realize power control of the pulse pump laser. The average optical power of the pulse pump laser output from the optical attenuator 4 is 0.49mW; the optical amplifier 3 uses an erbium-doped fiber amplifier, and the second adjustable optical attenuator 4 uses an adjustable fiber attenuator.

The pulse pump laser output from the second optical attenuator 4 is input to the polarization controller 5 to realize polarization control of the pulse pump laser;

The pulse pump laser output from the polarization controller 5 is input to the polarizer 6, and the pulse pump laser output from the polarizer 6 is linearly polarized light; by changing the working state of the polarization controller 5, the pulse pump laser output from the polarizer 6 can be The power of the pulse pump laser reaches its maximum. The polarization controller 5 adopts an optical fiber polarization controller, and the polarizer 6 adopts an optical fiber polarizer.

Under the action of pump light, the nonlinear crystal waveguide (7) undergoes a spontaneous parametric down-conversion process to generate broad-spectrum signal photons with bandwidths covering wavelengths λ _s1 , λ _s2 ...λ _sn and bandwidths covering wavelengths λ _i1 , λ _i2 ...λ _in broad spectrum idler photon, signal photon with wavelength λ _sk (k=1, 2,...n) and idler photon with wavelength λ _ik (k=1, 2,...n) There is quantum correlation or quantum entanglement between them. In this embodiment, the linearly polarized pulse pump laser output from the polarizer 6 is input into the nonlinear crystal waveguide 7, and the nonlinear crystal waveguide 7 adopts a periodically polarized lithium niobate waveguide. In the nonlinear crystal waveguide 7, the pulse pump laser with the center wavelength of 1540.60 nm first generates the pulse pump laser with the center wavelength of 770.30 nm through the second harmonic generation process, and the latter generates the center wavelength at 1540.60 through the spontaneous parametric down-conversion process. nm, photon pairs with a spectral width greater than 60nm, one of each photon pair is a signal photon and the other is an idler photon. According to the principle of spontaneous parametric down-conversion process, there is a quantum correlation between signal photons and idler photons.

The quantum correlation/entanglement photon pairs generated in the nonlinear crystal waveguide 7 are output from it, and then input into the second optical isolator 8; the quantum correlation/entanglement photon pairs output from the second optical isolator 8 are input into the first dense wave division complex The common terminal (C terminal) of user 9.

The first dense wavelength division multiplexer 9 and the second dense wavelength division multiplexer 11 are respectively used to filter out wide spectrum signal photons and idler photons; the N of the first optical filter 10 (N≤n ) The kth (k=1,...N) port among the output ports is used to output signal photons with a central wavelength of λ _sk , and there is no spectrum overlap among the signal photons output by the N output ports; in this embodiment, the first The transmission end (T end) of the dense wavelength division multiplexer 9 outputs signal photons with a central wavelength of 1549 nm and a bandwidth of 100 GHz, and the reflection end (R end) outputs photons whose wavelength is not within the transmission wavelength range of the transmission end;

The signal photons output from the transmission end of the first dense wavelength division multiplexer 9 are input to the first optical filter 10. The five output ends of the first optical filter 10 respectively output signal photons of five frequency modes. The bandwidth of each frequency mode is 10GHz, the center frequency interval of adjacent frequency modes is 15GHz;

The photons output from the reflection end (R end) of the first dense wavelength division multiplexer 9 are input to the second dense wavelength division multiplexer 11, and the transmission end (T end) of the second dense wavelength division multiplexer 11 outputs a center wavelength of 1532 nm , idler photons with a bandwidth of 100 GHz; the idler photons output from the transmission end (T end) of the second dense wavelength division multiplexer 11 are input to the second optical filter 12 .

The kth (k=1, 2,...n) port among the N output ports of the second optical filter (12) is used to output idler photons with a central wavelength of λ _ik , and the N output ports output There is no spectrum overlap for idler photons; in this embodiment, the five output terminals of the second optical filter 12 respectively output idler photons in five frequency modes. The bandwidth of each frequency mode is 10 GHz, and the center frequencies of adjacent frequency modes are spaced apart. to 15GHz. The signal photons output from the jth (j=1,2...5) output terminal of the first optical filter 10 and the jth (j=1,2...5) output from the second optical filter 12 The idler photons output from the terminal constitute a pair of quantum correlated/entangled photons;

The transmission center wavelength of the kth (k=1, 2,...N) transmission end (T end) of the third dense wavelength division multiplexer (13) is λ _ik (k=1,...N) , realizing multi-frequency mode multiplexing of idler frequency photons input by N transmission terminals (T terminals); in this embodiment, the idler frequency photons of five frequency modes output by the second optical filter 12 are input into the third dense wavelength division complex The five transmission ends (T end) of the device 13 are all emitted from the common end (C end) of the third dense wavelength division multiplexer 13, thereby realizing the multiplexing of idler photons in five frequency modes.

The second optical isolator 14 is used to block the pump light of the atomic frequency comb prepared in the erbium-doped solid material 22 from entering the broadband multi-frequency mode multiplexed communication band quantum correlation source or quantum entanglement source.

The first optical isolator 8 and the second optical isolator 14 adopt optical fiber isolators, and the first dense wavelength division multiplexer 9 , the second dense wavelength division multiplexer 11 and the third dense wavelength division multiplexer 13 adopt diaphragms. Type Dense Wavelength Division Multiplexer, the first optical filter 10 and the second optical filter 12 adopt five-level cascaded fiber Bragg gratings.

The optical frequency comb output from the optical switch 19 enters the first optical attenuator 20 to achieve power adjustment. The optical frequency comb output from the first optical attenuator 20 is incident on the first port of the optical circulator 21 , emerges from the second port of the optical circulator 21 , and then is incident on the erbium-doped solid material 22 . As pump light, the optical frequency comb interacts with the erbium ion ensemble in the erbium-doped solid material 22 to excite the corresponding erbium ions, and the remaining ground state erbium ions form an atomic frequency comb with five frequency domain modes. The frequency domain bandwidth of each frequency comb of the atomic frequency comb is 10GHz, the comb tooth spacing of the atomic frequency comb of each mode is 50MHz, and the spacing between adjacent frequency modes is 5GHz. Figure 2 is the experimentally measured absorption spectrum of the atomic frequency comb of five channels in the erbium-doped solid material 22. It can be seen from Figure 2 that the mode bandwidth of each atomic frequency comb is 10GHz, and the width between adjacent comb teeth in the mode is 50MHz;

The idler photons of the five frequency modes output by the second optical filter 12 are input to the five transmission terminals (T terminals) of the third dense wavelength division multiplexer 13 , and are all connected from the common terminal of the third dense wavelength division multiplexer 13 (Terminal C) is emitted from the common terminal (Terminal C) of the third dense wavelength division multiplexer 13. After the multi-frequency mode multiplexed idler photons enter the erbium-doped solid material 22 through the second optical isolator 14, they become coherent. stored in the multi-channel atomic frequency comb, since the signal photon output from the kth (k=1,...N) output port of the first optical filter 10 and the kth input to the third dense wavelength division multiplexer 13 There is quantum correlation or quantum entanglement between the idler photons output from the (k=1,...N) transmission ends (T end) and their common end (C end), and the idler photons are stored in the atomic frequency comb The process is a coherent interaction, so there is quantum correlation or entanglement between the multi-channel atomic frequency comb that stores multi-frequency mode multiplexed idler photons and the multi-channel signal photons, that is, a multi-channel broadband light-atom interface is achieved.

In the example:

1. 15: The laser source is an external cavity semiconductor laser.

2. 16: The intensity modulator is a lithium niobate electro-optical intensity modulator.

3: The optical amplifier is an erbium-doped fiber amplifier

4. 20: The adjustable attenuator is an adjustable optical fiber attenuator

5: The polarization controller is a fiber polarization controller

6: The polarizer is an optical fiber polarizer.

7: The nonlinear crystal waveguide is a periodically polarized lithium niobate waveguide.

8. 14: The optical isolator is a fiber optic isolator.

9, 11, 13: The dense wavelength division multiplexer is a diaphragm type dense wavelength division multiplexer.

10, 12: The optical filter is a five-stage cascade fiber Bragg grating.

17, 18: The phase modulator is a lithium niobate electro-optical phase modulator.

19: Optical switch is a 1×2 MEMS optical fiber switch

21: Optical circulator is a fiber optic circulator

22: The erbium-doped solid material is an erbium-doped optical fiber located in a 10mK temperature environment and a 0.3T magnetic field.

Optionally, the erbium-doped solid material 22 is an erbium-doped lithium niobate crystal, an erbium-doped yttrium silicate crystal, an erbium-doped quartz fiber, or an erbium-doped gadolinium vanadate crystal.

Optionally, the first laser source 15 and the second laser source 1 are solid-state laser sources, gas laser sources, semiconductor laser sources or dye laser sources.

Optionally, the first intensity modulator 16 and the second intensity modulator 2 are intensity modulators based on the acousto-optic effect or the electro-optic effect;

And/or, the first optical phase modulator 17 and the second optical phase modulator 18 are electro-optical phase modulators using KDP crystal or lithium niobate crystal as the electro-optical crystal.

Optionally, the first dense wavelength division multiplexer 9, the second dense wavelength division multiplexer 11 and the third dense wavelength division multiplexer 13 are thin film type dense wavelength division multiplexers or volume grating type dense wavelength division multiplexers. device, arrayed waveguide grating type dense wavelength division multiplexer or fiber grating type dense wavelength division multiplexer.

Optionally, the first optical filter 10 and the second optical filter 12 are fiber Bragg grating filters, cascaded fiber Bragg grating filters or volume grating filters;

And/or, the polarization controller 5 is a wave plate polarization controller or an optical fiber polarization controller.

The present invention combines optical frequency comb generation technology and frequency chirp control technology to prepare multi-channel broadband atomic frequency combs in erbium-doped solid materials, and uses the multi-channel broadband atomic frequency comb to perform quantum correlation for broadband multi-frequency multiplexing of optical communication bands. Or one photon in the entangled photon pair is stored in time domain multi-mode, thereby establishing the quantum correlation or entanglement between the other photon and the atomic frequency comb, forming a light-atom interface. Each component used in the present invention to prepare multi-channel broadband light-atom interfaces can be derived from mature optoelectronic devices, which is conducive to the development of practical quantum network nodes based on light-atom interfaces. The light-atom interface prepared by this method has the advantages of large bandwidth and multi-channel, and can be widely used in fields such as quantum communication and quantum entanglement networks.

In the description of this specification, reference to the terms "one embodiment," "some embodiments," "an example," "specific examples," or "some examples" or the like means that specific features are described in connection with the embodiment or example. , structures, materials or features are included in at least one embodiment or example of the invention. In this specification, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and combine different embodiments or examples and features of different embodiments or examples described in this specification unless they are inconsistent with each other.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (10)

1. A multi-channel broadband optical communication band optical-atom interface preparation device, characterized in that it includes a multi-channel broadband atomic frequency comb preparation device and a multi-frequency mode multiplexed optical communication band quantum correlation source or quantum entanglement source, 2. are connected through optical fiber; The multi-channel broadband atomic frequency comb preparation device uses optical frequency comb generation technology and frequency chirp control technology to prepare multi-channel broadband atomic frequency combs in erbium-doped solid materials; The multi-frequency mode multiplexed optical communication band quantum correlation source or quantum entanglement source generates multi-frequency mode multiplexed quantum correlation photon pairs or quantum entangled photon pairs through periodically polarized lithium niobate waveguides, and the atomic frequency comb pairs One photon in the quantum correlated photon pair or the quantum entangled photon pair is stored in a time domain multi-mode, and a quantum correlation between the other photon in the quantum correlated photon pair or the quantum entangled photon pair and the atomic frequency comb is established, or Quantum entanglement forms a multi-channel bandwidth optical communication band light-atom interface. 2. A multi-channel broadband optical communication band optical-atom interface preparation device according to claim 1, characterized in that the multi-channel broadband atomic frequency comb preparation device includes first laser sources (15) connected in sequence , the first light intensity modulator (16), the first light phase modulator (17), the second light phase modulator (18), the light switch (19) and the first adjustable light attenuator (20), the One end of the first adjustable light attenuator (20) is connected to the optical switch (19), and the other end of the first adjustable light attenuator (20) is connected to the first port of the optical circulator (21). The second port of the device (21) is connected to one end of the erbium-doped solid material (22); The first laser source (15) is used to provide continuous and stable pump light; The light intensity modulator (16) and the first optical phase modulator (17) are used to modulate the pump light output by the first laser source (15) into an optical frequency comb with several comb teeth; The second optical phase modulator (18) is used to load the optical frequency comb with periodic frequency shifting signals. In each cycle, the comb teeth will be frequency shifted several times at equal intervals. After each comb tooth undergoes periodic frequency shifting, The interval is a frequency domain mode, and an optical frequency comb with several comb-like teeth becomes a multi-mode pump light; The first adjustable optical attenuator (20) is used to adjust the power of pump light. 3. A device for preparing a multi-channel broadband optical communication band light-atom interface according to claim 1, characterized in that the multi-frequency mode multiplexed quantum correlation source or quantum entanglement source includes second lasers connected in sequence. Source (1), second light intensity modulator (2), optical amplifier (3), second adjustable optical attenuator (4), polarization controller (5), polarizer (6), nonlinear crystal waveguide (7), first optical isolator (8); One end of the first optical isolator (8) is connected to the nonlinear crystal waveguide (7), and the other end of the first optical isolator (8) is connected to the common end (C) of the first dense wavelength division multiplexer (9). end) are connected, the transmission end (T end) of the first dense wavelength division multiplexer (9) is connected to one end of the first optical filter (10), the reflection end of the first dense wavelength division multiplexer (9) The end (R end) is connected to the common end (C end) of the second dense wavelength division multiplexer (11), and the transmission end (T end) of the second dense wavelength division multiplexer (11) is connected to the second optical filter The input terminals of the second optical filter (12) are connected to each other, and the N output terminals of the second optical filter (12) are connected to the N transmission terminals (T terminals) of the third dense wavelength division multiplexer (13). The common end (C end) of the dense wavelength division multiplexer (13) is connected to one end of the second optical isolator (14), and the other end of the second optical isolator (14) is connected to the multi-channel broadband atomic frequency comb. One end of the erbium-doped solid material (22) in the preparation device is connected. 4. A multi-channel broadband optical communication band light-atom interface preparation device according to any one of claims 1 to 3, characterized in that the erbium-doped solid material (22) is an erbium-doped lithium niobate crystal, Erbium-doped yttrium silicate crystal, erbium-doped silica fiber or erbium-doped gadolinium vanadate crystal. 5. A multi-channel broadband optical communication band optical-atom interface preparation device according to any one of claims 1 to 3, characterized in that the first laser source (15) and the second laser source (1) It is a solid-state laser source, a gas laser source, a semiconductor laser source or a dye laser source. 6. A multi-channel broadband optical communication band optical-atom interface preparation device according to any one of claims 1-3, characterized in that the first intensity modulator (16) and the second intensity modulator (16) 2) It is an intensity modulator based on the acousto-optic effect or the electro-optic effect; And/or, the first optical phase modulator (17) and the second optical phase modulator (18) are electro-optical phase modulators using KDP crystal or lithium niobate crystal as the electro-optical crystal. 7. A multi-channel broadband optical communication band optical-atom interface preparation device according to any one of claims 1 to 3, characterized in that the first dense wavelength division multiplexer (9), the second dense wavelength division multiplexer (9), The multiplexer (11) and the third dense wavelength division multiplexer (13) are a thin film type dense wavelength division multiplexer, a volume grating type dense wavelength division multiplexer, an arrayed waveguide grating type dense wavelength division multiplexer or an optical fiber Grating type dense wavelength division multiplexer. 8. A multi-channel broadband optical communication band optical-atom interface preparation device according to any one of claims 1 to 3, characterized in that the first optical filter (10), the second optical filter ( 12) It is a fiber Bragg grating filter, a cascaded fiber Bragg grating filter or a volume grating filter; And/or, the polarization controller (5) is a wave plate polarization controller or an optical fiber polarization controller. 9. A method for preparing a multi-channel broadband optical communication band light-atom interface, which is realized by using the multi-channel broadband optical communication band light-atom interface preparation device according to any one of claims 1 to 8, characterized in that: Following steps: Use optical frequency comb generation technology and frequency chirp control technology to prepare multi-channel broadband atomic frequency combs in erbium-doped solid materials; The atomic frequency comb performs time-domain multi-mode storage of one photon in a quantum correlated photon pair or a quantum entangled photon pair in the optical communication band multiplexed in a broadband multi-frequency mode, and establishes the quantum correlated photon pair or quantum entangled photon pair. The quantum correlation or quantum entanglement between another photon and the atomic frequency comb forms a multi-channel broadband optical communication band light-atom interface. 10. A method for preparing a multi-channel broadband optical communication band optical-atom interface according to claim 9, characterized in that the preparation method of the atomic frequency comb specifically includes the following steps: The optical frequency comb technology is used to generate an optical frequency comb with several comb teeth. The frequency chirp control technology is used to cause the optical frequency comb to generate periodic frequency shifts. In each cycle, the comb teeth are frequency shifted several times at equal intervals. Each comb tooth The interval after periodic frequency shifting is a frequency domain mode. An optical frequency comb with several comb-like teeth becomes a multi-mode pump light. The multi-mode pump light pumps the erbium-doped solid-state material. The pump light and doped solid-state material The erbium ion ensemble in the erbium solid material interacts, and the spectral hole burning principle is used to excite the corresponding erbium ions in the erbium-doped solid material, and the remaining ground state erbium ions form a multi-channel atomic frequency comb.