CN100485511C - Evanescent wave optical fiber amplifier for quantum spot semiconductor nano-materials and manufacture method thereof - Google Patents

Abstract

The invention relates to a quantum dot semiconductor nano material evanescent wave optical fiber amplifier and a manufacturing method thereof. It uses the fused cone fiber coupler as the amplifying fiber for the evanescent wave amplification of the fiber, and coats the outside of the fused cone coupling area with nano-scale semiconductor materials, thereby realizing the evanescent wave fiber amplification effect coupled with nano-semiconductor materials. It consists of a pumping light source and a signal light source connected to a quantum dot semiconductor nanomaterial evanescent wave amplifying fiber. The method is as follows: firstly, an optical fiber coupling device is made, then quantum dot semiconductor nanometer material is made, then quantum dot semiconductor nanometer material evanescent wave amplifying optical fiber is made, and finally an amplifier system is made. The quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier realizes wide spectrum, small size and low price, and can be widely used in long-distance, large-capacity, high-speed communication systems, access networks, optical fiber CATV networks, FTTH, military systems Optical signal amplification in fields such as optical fiber sensors can also be used for optical signal amplification in the field of optical fiber sensors.

Description

Quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier and manufacturing method thereof

technical field

The invention relates to a quantum dot semiconductor nano material evanescent wave optical fiber amplifier and a manufacturing method thereof, belonging to the technical fields of optical communication technology and nano material preparation.

Background technique

Nanomaterials are the most dynamic field of new material research today. Due to the quantum size, surface, and macroscopic quantum tunneling effects of nanoparticles, compared with micron crystals of the same material, they have many strange properties in terms of catalysis, optics, magnetism, mechanics, and biology. Nanotechnology is the common basis for the further development of information technology and life science and technology in the future. The use of nanomaterials to develop special functional optical fiber devices is the product of the combination of nanotechnology and information technology. Among them, the broadband optical fiber amplifier urgently needed in the field of optical fiber communication is a combination point of nanotechnology and optical communication technology. Optical fiber amplifiers are one of the most important components in high-speed, large-capacity optical fiber communication networks. With the continuous increase of dense wavelength division multiplexing (DWDM) channels and the rapid application of fiber-to-the-home (FTTH), the requirements for optical fiber amplifiers are also increasing. Higher and higher, it requires the fiber amplifier to develop in the direction of wide bandwidth and miniaturization, but the commonly used amplifier (EDFA) based on erbium-doped rare earth element fiber is due to its long fiber length (about 30m) and narrow amplification spectrum width (about 30nm) can no longer meet the growing needs of optical fiber communication. In addition, optical fiber amplifiers with low price and strong engineering are also pursued by optical fiber communication systems.

Contents of the invention

The object of the present invention is to provide a novel quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier aiming at the defects in the prior art. It has the function of amplifying optical signals and solves the problem that doped rare earth fibers must use long optical fibers (meter level) to achieve optical signal amplification, and it can use shorter (centimeter level) optical fibers to achieve optical signal amplification.

The second object of the present invention is that the quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier has broadband characteristics, which is about 3 to 5 times of the bandwidth of common erbium-doped optical fiber.

Another object of the present invention is to propose a set of practical and feasible quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier manufacturing in terms of optical fiber manufacturing technology and process flow based on the existing optical fiber preparation technology, combined with nanometer manufacturing technology and process methods method.

In order to achieve the above object, design of the present invention is:

The present invention proposes a novel quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier, which is based on nanomaterial technology, semiconductor theory, light wave coupling theory and optical fiber evanescent wave theory, and uses a fused-cone fiber coupler as an optical fiber evanescent wave amplifier. The amplified amplified optical fiber is realized by coating the outside of the fusion cone coupling region with nano-scale semiconductor material.

According to above-mentioned inventive concept, the present invention adopts following technical scheme:

A quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier is composed of a pump light source and a signal light source connected to an evanescent wave amplifying optical fiber, and is characterized in that the evanescent wave amplifying optical fiber is quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier. Evanescent wave amplification fiber, which is composed of 2×2 fused-taper fiber coupling device, quantum dot semiconductor nanomaterials and packaging protection tube, the 2×2 fused-taper fiber coupling device consists of pump light input fiber and signal light input fiber The two fiber ends of the input end of a 2×2 fused-taper fiber coupling area are respectively connected, and the two fiber ends of the output end of the 2×2 fused-taper fiber coupling area are respectively connected to the amplified signal output fiber and the amplified pump output fiber. Composition; the quantum dot semiconductor nanomaterial is placed in the packaging protection tube, and surrounds the 2 × 2 fusion tapered fiber coupling area; the two ends of the packaging protection tube have packaging glue to seal the quantum dot semiconductor nanomaterial in the Between the packaging protection tube and the 2×2 tapered fiber coupling area.

In the aforementioned quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier, the quantum dot semiconductor nanomaterial evanescent wave optical fiber can be single-mode or multimode optical fiber according to the requirements of technical parameters.

In the above-mentioned quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier, the quantum dot semiconductor nanomaterial can adopt different semiconductor materials according to actual needs, such as PSe, CdSe, CdS, InP, PbSe, ZnSe, ZnS Choose one of HgTe.

A method for manufacturing an evanescent wave optical fiber amplifier with quantum dot semiconductor nanomaterials, which is characterized in that firstly, the fusion taper technology is used to make a 2 × 2 fusion tapered optical fiber coupling device; then the quantum dot semiconductor nanomaterial is prepared; and then the quantum dot semiconductor nanometer The materials are combined with 2×2 fused tapered optical fiber coupling devices and packaged to form the quantum dot semiconductor nanomaterial evanescent wave amplification fiber; finally, the pump light source 1, the signal light source 2 and the quantum dot semiconductor nanomaterial evanescent wave Wave amplifying optical fiber 3 forms optical fiber amplifier; Its concrete technological process and technological steps are as follows:

(1) Fabrication of 2×2 fused-taper fiber coupling devices using fused tapered technology:

Two optical fibers are drawn into a 2×2 fused-cone fiber coupling device with a fusion tapered machine, and the coupling device consists of pump light input fiber, signal light input fiber, 2×2 fused-taper fiber coupling area, and amplified signal output Composed of optical fiber and amplified pump output fiber, the fiber length of pump light input fiber, signal light input fiber, amplified signal output fiber and amplified pump output fiber is 1-2 meters, 2×2 fused cone fiber coupling area The length is 2 to 3 cm;

(2) Preparation of quantum dot semiconductor nanomaterials by sol-gel method:

1) Ethyl orthosilicate TEOS is subjected to acid hydrolysis for 1.2 to 1.8 hours, the ratio of ethyl orthosilicate, water, ethanol and nitric acid is 1:1:1:2.7×10 ^-3 , methanol solution, methanol and lead The ratio of the salt Pb(Ac) ₂ 3H ₂ O is 15.8:1. It is introduced into the hydrolyzed solution of ethyl orthosilicate and dispersed evenly for 1.2 to 1.8 hours. Add ammonia water, ethanol and water at a ratio of 0.05:1: 4. Carry out basic hydrolysis again, and after uniform mixing, a clear and transparent homogeneous sol is obtained;

2) Pass the obtained sol into hydrogen sulfide gas at a temperature of 150°C±15°C, and react for 0.45 to 0.55 hours to obtain a PbS/SiO2 quantum semiconductor nanomaterial;

(3) Preparation of quantum dot semiconductor nanomaterial evanescent wave amplification optical fiber:

1) Put the packaging protection tube on the 2×2 fusion cone fiber coupling area, so that the 2×2 fusion cone fiber coupling area is in the packaging protection tube, and then seal one end with packaging glue;

2) Put the quantum semiconductor nanomaterials into the packaging protection tube, and surround the 2×2 fusion cone fiber coupling area;

3) Seal the other end of the 2×2 fused-taper fiber coupling device with encapsulant, that is, form the quantum dot semiconductor nanomaterial evanescent wave amplification optical fiber;

(4) Made into optical fiber amplifier:

Connect the pump light source to the pump light input fiber of the quantum dot semiconductor nanomaterial evanescent wave amplification fiber, and connect the signal light source to the signal light input fiber of the quantum dot semiconductor nanomaterial evanescent wave amplification fiber. At this time, the signal output after amplification The signal obtained by the optical fiber is the optically amplified signal, and the optical signal output by the pump output fiber after amplification is the remaining pumping optical signal after the pumping light is absorbed by the amplifier.

In the manufacturing method of the above quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier, the quantum dot semiconductor nanomaterial evanescent wave amplifying optical fiber can be single-mode or multimode optical fiber according to the requirements of technical parameters.

The above-mentioned manufacturing method of quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier, described quantum dot semiconductor nanomaterial can adopt different semiconductor materials according to actual needs, such as PSe, CdSe, CdS, InP, PbSe, ZnSe , ZnS and HgTe any one.

The principle of the inventive method is as follows:

The amplification mechanism of this quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier of the present invention is to utilize the amplifying optical fiber of the evanescent wave amplification of the fused-cone fiber coupler, and coat the fused-cone outer layer with nano-scale semiconductor material realized. When the pump light and the signal light pass through the evanescent wave semiconductor cone region with coupling effect, once the incident pump photon energy is greater than the semiconductor band gap, strong intrinsic absorption will occur, and the incident photon will absorb the electrons in the semiconductor valence band Excitation makes a vertical transition into the conduction band, so that when the signal light wave passes through the semiconductor nanomaterial in this state, the signal light is amplified.

Because the semiconductor nanoparticles are embedded in the medium, when their scale is the quantum scale (that is, smaller than the Bohr radius of the bound excitons in the semiconductor material) (also known as the quantum size effect), a quantum dot structure is formed. The emergence of quantum dot semiconductor nanomaterials confines electrons within the point-like structure, realizing zero-dimensional quantum confinement. As a result, quantized energy levels with a certain energy interval will be formed between the conduction band and the valence band, and the smaller the size of the quantum dot, the larger the distance between the quantized energy levels, the stronger the ability to absorb the pump beam, and the higher energy The number of particle inversions formed on the belt is stronger. When a small signal light of a certain wavelength is coupled to the quantum dot semiconductor nanomaterial, a large number of photogenerated carriers will be induced to relax from a higher quantized energy level to a lower quantized energy level, forming a stimulated emission process. , which increases the probability of generating stimulated emission photons, which improves the amplification performance and enables the signal to be amplified with enhancement.

From the above, it can be seen that the quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier of the present invention is a new type of optical fiber amplifier that is integrated, has a wide gain spectrum, is easy to use, and is cheap.

Compared with the prior art, the present invention has the following obvious outstanding substantive features and significant advantages:

The evanescent wave optical fiber amplifier realized by the present invention adopts the double-fiber fusion cone form in structure, and the amplifying material adopts quantum dot nano-semiconductor. Compared with the rare earth-doped optical fiber amplifier, it has advantages in bandwidth, volume and price . The specific advantages are as follows: (1) Quantum dot semiconductor is used as an amplifying material, and its particle transition does not occur between discrete energy levels, but between two energy bands (valence band and conduction band), so the amplified The spectral width is much wider than that of rare-earth-doped fiber, about 3-5 times that of traditional erbium-doped fiber amplifiers; (2) Nano-semiconductor materials do not have strict requirements on the wavelength of the pump light source, so the pump light source is not necessarily The requirement is a laser, and devices such as light-emitting diode arrays can also be used; (3) its amplified optical fiber area is in the centimeter range, and the lead end of the amplified area can be used as the input and output of pump and signal light, small in size and low in cost .

As an optical fiber amplifier, the present invention is suitable for optical signal amplification in long-distance, large-capacity, high-speed communication systems, access networks, optical fiber CATV networks, FTTH, military systems, and other fields, and can also be used for optical signal amplification in the field of optical fiber sensors .

Description of drawings:

Fig. 1 is a schematic diagram of the structure and principle of an evanescent wave optical fiber amplifier made of quantum dot semiconductor nanomaterials according to the present invention.

Fig. 2 is a schematic diagram of the structure of an evanescent wave amplifying optical fiber made of quantum dot semiconductor nanomaterials.

Detailed ways

A preferred embodiment of the present invention is described below in conjunction with accompanying drawing:

This quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier is composed of a 980nm pump light source 2, a 1310nm signal light source 1 and a quantum dot PbS semiconductor nanomaterial evanescent wave amplification fiber 3, as shown in Figure 1, its quantum dot semiconductor nanomaterial evanescent wave amplifier The evanescent wave amplifying fiber 3 is composed of a 2×2 fused-cone single-mode fiber coupling device, a quantum dot semiconductor nanomaterial 34 and a package protection tube 35, wherein the 2×2 fused-cone single-mode fiber coupling device is composed of a pump light input fiber 31, The signal light input optical fiber 32, the 2×2 fusion taper optical fiber coupling area 39, the amplified signal output optical fiber 37 and the amplified pump output optical fiber 38 are composed of the quantum dot PbS semiconductor nanomaterial 34 placed in the quartz packaging protection tube 35, and Surrounding the 2×2 fused-taper fiber coupling region 39 , encapsulation glue 33 and 36 seal the quantum dot semiconductor nanomaterial 34 between the quartz package protection tube 35 and the 2×2 fused-taper fiber coupling region 39 .

The manufacturing method of this quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier comprises the following steps, referring to Fig. 2:

(1) Using fused tapered technology to make 2×2 fused tapered single-mode fiber coupling devices:

Two single-mode optical fibers are drawn into a 2×2 fused-taper fiber coupling device with a fusion tapered machine, and the coupling device is composed of a pump light input fiber 31, a signal light input fiber 32, and a 2×2 fused-taper fiber coupling area 39 , an amplified signal output optical fiber 37 and an amplified pump output optical fiber 39, the optical fiber length of the pump light input optical fiber 31, the signal light input optical fiber 32, the amplified signal output optical fiber 37 and the amplified pump output optical fiber 38 is 1 meter , the length of the 2×2 fused-taper fiber coupling region 39 is 3 cm.

(2) Using the sol-gel (sol-gel) method to prepare quantum dot PbS semiconductor nanomaterials:

1) Ethyl orthosilicate TEOS was subjected to acid hydrolysis for 1.5 hours, the ratio of ethyl orthosilicate, water, ethanol and nitric acid was 1:1:1:2.7×10 ^-3 , methanol solution, methanol and lead salt ( The ratio of Pb(Ac) ₂ 3H ₂ O) is 15.8:1, introduced into the acid hydrolyzate of orthosilicate acetate, and dispersed evenly for 1.5 hours, adding ammonia, ethanol, water, the ratio is 0.05:1:4, Carry out alkaline hydrolysis again, after mixing evenly, obtain the homogeneous sol with clear surface, transparent;

2) Pass the sol into hydrogen sulfide gas at a temperature of 150° C., and react for 0.5 hour to obtain the PbS/SiO2 quantum semiconductor nanomaterial 34 .

(3) Preparation of quantum dot semiconductor nanomaterial evanescent wave amplification optical fiber:

1) Put the quartz packaging protective sleeve 35 on the 2×2 fused-taper fiber coupling region 39, so that the 2×2 fused-taper fiber coupling region 39 is in the packaging protection tube 35, and then seal one end with a packaging glue 33;

2) Put the quantum PbS semiconductor nanomaterial 34 into the quartz package protection tube 35, and surround the 2×2 fusion tapered fiber coupling area 39;

3) Seal the other end of the 2×2 fused-taper fiber coupling device with encapsulant 36 , that is, form the evanescent-wave amplifying optical fiber 3 made of quantum dot semiconductor nanomaterials.

(4) Made into optical fiber amplifier:

Connect the 980nm pump light source 1 with the pump light input fiber 31 of the quantum dot semiconductor nanomaterial evanescent wave amplification fiber 3, and connect the 1310nm signal light source 2 with the signal light input fiber 32 of the quantum dot semiconductor nanomaterial evanescent wave amplification fiber 3 At this time, the signal obtained by the signal output optical fiber 37 after amplification is the optical amplified signal, and the amplification gain of the signal is about 4-5 dB.

Quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier The quantum dot semiconductor nanomaterial evanescent wave amplifying optical fiber 3 uses a single-mode optical fiber with a core of 9 μm and a fiber diameter of 125 μm.

Claims (3)

1. A quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier is formed by connecting a pump light source (1) and a signal light source (2) with an evanescent wave amplification optical fiber, and is characterized in that described evanescent wave amplification The optical fiber is a quantum dot semiconductor nanomaterial evanescent wave amplifying optical fiber (3), which is composed of a 2×2 fused-taper fiber coupling device, a quantum dot semiconductor nanomaterial (34) and a packaging protection tube (35), and the 2× 2 Fused-tapered optical fiber coupling device is respectively connected to two fiber ends of the input end of a 2×2 fused-tapered fiber coupling area (39) by pumping light input fiber (31) and signal light input fiber (32), and 2×2 fused The two fiber ends of the output end of the tapered fiber coupling area (39) are respectively connected to the amplified signal output fiber (37) and the amplified pump output fiber (38); the quantum dot semiconductor nanomaterial (34) is placed In the encapsulation protection tube (35), and surround 2 * 2 melting taper fiber coupling regions (39); The two ends of the encapsulation protection tube (35) have encapsulation glue (33, 36) to put the quantum dot semiconductor nano The material (34) is sealed between the packaging protection tube (35) and the 2×2 fusion tapered fiber coupling region (39). 2. The quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier according to claim 1, characterized in that the optical fiber used in the quantum dot semiconductor nanomaterial evanescent wave optical fiber (3) is a single-mode or multimode optical fiber. 3. quantum dot semiconductor nanomaterial evanescent wave optical fiber amplifier according to claim 1, is characterized in that described quantum dot semiconductor nanomaterial (34) is PSe, CdSe, CdS, InP, PbSe, ZnSe, ZnS and HgTe Choose one of them.