CN102540623A

CN102540623A - Scheme and device for increasing gain of optical fiber parametric amplifier by adopting phase-shifting grating

Info

Publication number: CN102540623A
Application number: CN2012100435682A
Authority: CN
Inventors: 朱宏娜; 罗斌; 潘炜; 闫连山; 项水英; 温坤华
Original assignee: Southwest Jiaotong University
Current assignee: Southwest Jiaotong University
Priority date: 2012-02-24
Filing date: 2012-02-24
Publication date: 2012-07-04
Anticipated expiration: 2032-02-24
Also published as: CN102540623B

Abstract

The invention discloses a scheme and a device for improving the gain of an optical fiber parametric amplifier by using a phase shift grating. The optical spectrum analyzer is composed of a relatively large distance between the wavelength of the pump light and the zero-dispersion wavelength of the optical fiber, and a phase shift grating is introduced between two sections of highly nonlinear optical fibers as a filter and a phase shifter for idler light. Reflection and phase shift are generated to compensate the phase mismatch in the fiber parametric process, thereby increasing the gain of the fiber parametric amplifier. The invention introduces a phase-shifting grating to realize higher parametric amplification, improves the gain of the optical fiber parametric amplifier, and is beneficial to the development of all-optical amplification technology in optical communication systems.

Description

Scheme and device for increasing gain of fiber parametric amplifier by using phase shift grating

技术领域 technical field

本发明涉及一种高增益光纤参量放大器，尤其是一种采用相移光栅实现增益提高的光纤参量放大器，适用于光纤通信和非线性光纤光学领域。 The invention relates to a high-gain optical fiber parametric amplifier, in particular to an optical fiber parametric amplifier which adopts a phase-shifting grating to realize gain improvement, and is suitable for the fields of optical fiber communication and nonlinear optical fiber optics. the

背景技术 Background technique

随着互联网数据业务的增多，光纤通信因其宽带、低损耗、抗电磁干扰等特点成为现在通信网络的主干，而能够实现全光信号放大技术的光放大器是光纤通信系统中的重要器件之一。其中，光纤参量放大器因为具有高增益带宽、高增益水平、饱和输出功率、高相敏特性以及多路任意波长信号同时放大的能力，受到了越来越多的关注，被认为是适合未来密集波分复用系统中最具前途的全光放大技术。提高增益是研究放大器的重要指标，因此，研究提高光纤参量放大器的增益成为极有吸引力的热点。 With the increase of Internet data services, optical fiber communication has become the backbone of the current communication network due to its characteristics of broadband, low loss, and anti-electromagnetic interference, and the optical amplifier that can realize all-optical signal amplification technology is one of the important devices in the optical fiber communication system. . Among them, the fiber parametric amplifier has received more and more attention because of its high gain bandwidth, high gain level, saturated output power, high phase sensitivity and the ability to simultaneously amplify multiple arbitrary wavelength signals, and is considered to be suitable for future dense wavelength division multiplexing. Use the most promising all-optical amplification technology in the system. Improving the gain is an important indicator of amplifier research. Therefore, research on increasing the gain of fiber parametric amplifiers has become a very attractive hotspot. the

就目前的研究进展而言，主要是通过让泵浦光波长工作在光纤的零色散波长附近以及采用几段高非线性光纤级联实现色散补偿等方式来提高光纤参量放大器的增益。但是，根据光纤通信系统的相应需要，也希望泵浦光波长工作在远离光纤的零色散波长，在一个相对大的波长范围内同样实现增益的提高。 As far as the current research progress is concerned, the gain of the fiber parametric amplifier is mainly improved by making the pump light wavelength work near the zero dispersion wavelength of the fiber and adopting several highly nonlinear fiber cascades to realize dispersion compensation. However, according to the corresponding needs of the optical fiber communication system, it is also hoped that the wavelength of the pump light works at the zero-dispersion wavelength far away from the optical fiber, and the gain can also be improved in a relatively large wavelength range. the

发明内容 Contents of the invention

鉴于以上陈述的已有技术的不足，本发明的目的是提出一种采用相移光栅来提高光纤参量放大器增益的方案及装置，在泵浦光波长和光纤零色散波长间隔为一个相对大的波长范围下，采用相移光栅插入在两段高非线性光纤间实现光纤参量放大器增益的提高。 In view of the deficiencies in the prior art stated above, the purpose of the present invention is to propose a scheme and a device for improving the gain of an optical fiber parametric amplifier by using a phase shift grating, and the interval between the pumping light wavelength and the zero dispersion wavelength of the optical fiber is a relatively large wavelength In the lower range, the gain of the fiber parametric amplifier is improved by inserting a phase-shifted grating between two sections of highly nonlinear fibers. the

本发明的目的是通过如下手段来实现的。 The purpose of the present invention is achieved by the following means. the

采用相移光栅提高光纤参量放大器增益的方案及装置，由外腔激光器、相位调制器、掺铒光纤放大器、偏振控制器、耦合器、相移光栅、高非线性光纤和光谱分析仪组成；包含如下的处理步骤：外腔激光器ECL1产生的泵浦光Pump1和外腔激光器ECL2产生的泵浦光Pump2依次分别经相位调制器PM1和PM2调制、掺铒光纤放大器EDFA1和EDFA2放大，以及偏振控制器PC1和PC2调整其偏振状态后，通过耦合器OC1耦合，一起与经过偏振控制器PC3调整的外腔激光器ECL3产生的信号光Signal耦合进入耦合器OC2，然后两个泵浦光和信号光同时进入高非线性光纤HNLF1，通过高非线性光纤中的参量过程实现闲频光的产生和信号光的放大，接着四个光波同时进入相移光栅PS-FBG，通过相移光栅对闲频光的部分滤波和相移实现参量过程的相位匹配，再进入高非线性光纤HNLF2后实现对信号光的再放大，利用光谱分析仪OSA1和OSA2测量相应功率的变化。本发明采用的相移光栅补偿相位失配实现了光纤参量放大器增益的提高。 A scheme and device for increasing the gain of a fiber parametric amplifier by using a phase-shift grating, consisting of an external cavity laser, a phase modulator, an erbium-doped fiber amplifier, a polarization controller, a coupler, a phase-shift grating, a highly nonlinear optical fiber, and a spectrum analyzer; including The following processing steps: the pumping light Pump1 generated by the external cavity laser ECL1 and the pumping light Pump2 generated by the external cavity laser ECL2 are respectively modulated by phase modulators PM1 and PM2, amplified by erbium-doped fiber amplifiers EDFA1 and EDFA2, and a polarization controller After PC1 and PC2 adjust their polarization states, they are coupled through the coupler OC1, and together with the signal light Signal generated by the external cavity laser ECL3 adjusted by the polarization controller PC3, they are coupled into the coupler OC2, and then the two pump lights and the signal light enter the coupler OC2 at the same time Highly nonlinear optical fiber HNLF1, through the parametric process in the highly nonlinear optical fiber, the generation of idler light and the amplification of signal light are realized, and then four light waves enter the phase shift grating PS-FBG at the same time, and the part of the idler light is transmitted through the phase shift grating Filtering and phase shifting realize the phase matching of the parametric process, and then re-amplify the signal light after entering the highly nonlinear fiber HNLF2, and use the optical spectrum analyzer OSA1 and OSA2 to measure the change of the corresponding power. The phase-shifting grating used in the invention compensates the phase mismatch and realizes the improvement of the gain of the optical fiber parametric amplifier. the

经过如上的设计后，利用一个相移光栅反射部分闲频光并对闲频光产生相应相移，调整了两个泵浦光、信号光和闲频光之间的相位失配参数，进而补偿了第一段光纤参量过程中的相位失配，提高了光纤参量放大器的增益并同时提高了泵浦光向信号光的能量转换效率。本发明具有如下优点：只需根据反射率和相移的需要来选择相应的光栅长度和相对折射率的相移光栅，就可以有效地提高光纤参量放大器的增益，本方案及装置简单容易实现，提高了光纤参量放大器的能量转换效率和系统灵活性。 After the above design, a phase-shift grating is used to reflect part of the idler light and generate a corresponding phase shift for the idler light, and adjust the phase mismatch parameters between the two pump light, signal light and idler light to compensate The phase mismatch in the first fiber parametric process is eliminated, the gain of the fiber parametric amplifier is improved and the energy conversion efficiency from pump light to signal light is improved at the same time. The present invention has the following advantages: the gain of the fiber parametric amplifier can be effectively improved only by selecting the corresponding grating length and relative refractive index phase shift grating according to the needs of reflectivity and phase shift, and the scheme and device are simple and easy to realize. The energy conversion efficiency and system flexibility of the optical fiber parametric amplifier are improved. the

附图说明如下： The accompanying drawings are as follows:

图1为本发明方案的系统框图。 Fig. 1 is a system block diagram of the solution of the present invention. the

图2为相移光栅的结构示意图，其中Λ为光栅周期，phase shift为相移。 Figure 2 is a schematic structural diagram of a phase shift grating, where Λ is the grating period, and phase shift is the phase shift. the

图3为π相移时相移光栅的(a)反射谱和(b)相移示意图。 Fig. 3 is a schematic diagram of (a) reflection spectrum and (b) phase shift of the phase shift grating when the phase is shifted by π. the

图4为两个泵浦光、闲频光和信号光的功率随光纤长度变化的示意图，其中实线为引入相移光栅的，点线为无相移光栅的。 Figure 4 is a schematic diagram of the power of two pump lights, idler light and signal light varying with the length of the fiber, where the solid line is the one with a phase-shifted grating introduced, and the dotted line is that without a phase-shifted grating. the

图5为光栅插入损耗和信号光增益的关系示意图。 Fig. 5 is a schematic diagram of the relationship between grating insertion loss and signal light gain. the

图6为信号光增益随光纤长度变化的关系示意图，其中实线为引入相移光栅的，点线为无相移光栅的。 Fig. 6 is a schematic diagram of the relationship between the signal light gain and the length of the optical fiber, wherein the solid line is the one with the phase shift grating introduced, and the dotted line is the one without the phase shift grating. the

具体实施方式Detailed ways

下面结合附图对本发明的实施作进一步的描述。 The implementation of the present invention will be further described below in conjunction with the accompanying drawings. the

如图1所示，本发明方案及装置，由外腔激光器ECL、相位调制器PM、掺铒光纤放大器EDFA、偏振控制器PC、耦合器OC、相移光栅PS-FBG、高非线性光纤HNLF和光谱分析仪OSA构成。相移光栅因其体积小、成本低和插入损耗低等优点在光纤通信与传感领域中的窄带滤波、波分复用/解复用、相移控制以及掺铒光纤增益平坦等方面有着广阔的应用前景。 As shown in Figure 1, the scheme and device of the present invention consist of an external cavity laser ECL, a phase modulator PM, an erbium-doped fiber amplifier EDFA, a polarization controller PC, a coupler OC, a phase shift grating PS-FBG, and a highly nonlinear optical fiber HNLF And optical spectrum analyzer OSA composition. Due to the advantages of small size, low cost and low insertion loss, phase shift gratings have broad applications in narrowband filtering, wavelength division multiplexing/demultiplexing, phase shift control, and gain flattening of erbium-doped fiber in the field of optical fiber communication and sensing. application prospects. the

在图1中，外腔激光器ECL1产生的波长λ_p1＝1480nm的泵浦光Pump1，与ECL2产生的波长λ_p2＝1620nm的泵浦光Pump2，分别经过相位调制器、掺铒光纤放大器和偏振控制器后耦合进入耦合器OC1，再与另一路外腔激光器ECL3产生的波长λ_s＝1520nm的信号光Signal一起耦合进耦合器OC2，在第一段光纤长度为60m零色散波长λ₀＝1550nm的高非线性光纤HNLF1中发生四波混频作用，产生波长为λ_i的闲频光Idler，同时对信号光进行放大。在光纤参量放大过程中两个泵浦光、信号光和闲频光间的角频率满足ω_p1+ω_p2＝ω_s+ω_i的条件。光纤距离较短时一般不考虑其传输损耗，并且在各个光波偏振态保持线偏振连续光的情况下，四个光波间的复振幅变化过程满足下面的耦合模方程： In Fig. 1, the pumping light Pump1 with the wavelength λ _p1 = 1480nm produced by the external cavity laser ECL1 and the pumping light Pump2 with the wavelength λ _p2 = 1620nm produced by the ECL2 pass through the phase modulator, the erbium-doped fiber amplifier and the polarization control respectively Coupled into the coupler OC1, and then coupled into the coupler OC2 together with the signal light Signal of the wavelength λ _s =1520nm generated by another external cavity laser ECL3, the first fiber length is 60m and the zero dispersion wavelength λ ₀ =1550nm Four-wave mixing occurs in the highly nonlinear fiber HNLF1 to generate idler light Idler with a wavelength of _λi and amplify the signal light at the same time. In the fiber parametric amplification process, the angular frequency between the two pump lights, signal light and idler light satisfies the condition of ω _p1 + ω _p2 = ω _s + ω _i . When the fiber distance is short, its transmission loss is generally not considered, and when the polarization state of each light wave maintains linearly polarized continuous light, the complex amplitude variation process among the four light waves satisfies the following coupling mode equation:

$\frac{d d {A A}_{p p 11}}{dz dz} = = iγ iγ [[(({| | {A A}_{p p 11} | |}^{22} + + 22 (({| | {A A}_{p p 22} | |}^{22} + + {| | {A A}_{s the s} | |}^{22} + + {| | {A A}_{i i} | |}^{22})))) {A A}_{p p 11} + + 22 {A A}_{p p 22} * * {A A}_{s the s} {A A}_{i i} {e e}^{iΔβz iΔβz}]] - - - - - - ((11))$

$\frac{d d {A A}_{p p 22}}{dz dz} = = iγ iγ [[(({| | {A A}_{p p 22} | |}^{22} + + 22 (({| | {A A}_{p p 11} | |}^{22} + + {| | {A A}_{s the s} | |}^{22} + + {| | {A A}_{i i} | |}^{22})))) {A A}_{p p 22} + + 22 {A A}_{p p 11} * * {A A}_{s the s} {A A}_{i i} {e e}^{iΔβz iΔβz}]] - - - - - - ((22))$

$\frac{d d {A A}_{s the s}}{dz dz} = = iγ iγ [[(({| | {A A}_{s the s} | |}^{22} + + 22 (({| | {A A}_{p p 11} | |}^{22} + + {| | {A A}_{p p 22} | |}^{22} + + {| | {A A}_{i i} | |}^{22})))) {A A}_{s the s} + + 22 {A A}_{i i} * * {A A}_{p p 11} {A A}_{p p 22} {e e}^{- - iΔβz iΔβz}]] - - - - - - ((33))$

$\frac{d d {A A}_{i i}}{dz dz} = = iγ iγ [[(({| | {A A}_{i i} | |}^{22} + + 22 (({| | {A A}_{p p 11} | |}^{22} + + {| | {A A}_{p p 22} | |}^{22} + + {| | {A A}_{s the s} | |}^{22})))) {A A}_{i i} + + 22 {A A}_{s the s} * * {A A}_{p p 11} {A A}_{p p 22} {e e}^{- - iΔβz iΔβz}]] - - - - - - ((44))$

其中A_p1，A_p2，A_s和A_i分别是两个泵浦光、信号光和闲频光的复振幅，γ是高非线性光纤的非线性系数，Δβ为线性波矢失配系数。 Among them, A _p1 , A _p2 , A _s and A _i are the complex amplitudes of the two pump lights, signal light and idler light respectively, γ is the nonlinear coefficient of the highly nonlinear fiber, and Δβ is the linear wave vector mismatch coefficient.

在HNLF1输出端连接一个相移光栅，相移光栅的结构如图2所示，其中Λ为光栅周期，通过调整相移光栅的长度和相对折射率等参数得到不同的反射系数和相移，作为滤波器和相移器的相移光栅把闲频光的波长设为光栅的布拉格相移波长，目的是减少闲频光的功率和产生相应相移。在图3中，在波长为1574.6nm处的闲频光的反射率为0.7，意味着只有大约30％的闲频光通过相移光栅，并且在闲频光波长处产生π的相移。但同时其他三个波长的光没有反射和额外相移的通过相移光栅。本方案中的相移光栅作为滤波器和相移器，改变了四个光波之间的相对相位差，进而实现相位匹配。 A phase-shift grating is connected to the output of HNLF1. The structure of the phase-shift grating is shown in Figure 2, where Λ is the grating period, and different reflection coefficients and phase shifts are obtained by adjusting the length and relative refractive index of the phase-shift grating, as The phase shift grating of the filter and the phase shifter sets the wavelength of the idler light to the Bragg phase shift wavelength of the grating, in order to reduce the power of the idler light and generate a corresponding phase shift. In Fig. 3, the reflectance of the idler light at the wavelength of 1574.6 nm is 0.7, which means that only about 30% of the idler light passes through the phase shift grating, and a phase shift of π occurs at the idler light wavelength. But at the same time the other three wavelengths of light pass through the phase shift grating without reflection and additional phase shift. The phase-shifting grating in this scheme acts as a filter and a phase shifter, changing the relative phase difference between the four light waves, thereby achieving phase matching. the

然后经过相位失配补偿的四个光波继续通过第二段高非线性光纤进行参量放大，实现了信号光功率的进一步放大，提高了光纤参量放大器的增益。其中高非线性光纤HNLF2与HNLF1除了光纤长度不同外，其余光纤参数性质都一致，此方案中HNLF2的长度为36m。图4说明了是否引入相移光栅时泵浦光1、泵浦光2、闲频光和信号光的功率随两段高非线性光纤长度变化的关系。可以看出输入功率都是2W的两个泵浦光和输入功率为1mW的信号光经过HNLF1后，通过参量放大过程，两个泵浦光的能量会向信号光和闲频光转移，在光纤长度60m处两个泵浦光的功率最低减少至1.24W，信号光的功率最大放大到0.75W，如果没有相移光栅的引入，随着光纤长度的增加，先前的泵浦光向信号光的能量转移方向发生变化，接着信号光的功率没有继续放大，反而继续较少至接近于0，同时泵浦光的功率逐渐增大到接近于输入功率，很显然，此时对于信号光的放大作用甚微。但是如果引入了相移光栅后，在光纤长度60m处，因为相移光栅对闲频光的反射作用，如图4(c)所示闲频光的功率从0.75W减少到0.22W，并且产生π的相移，进而对参量过程中的相位失配起到补偿作用。在此情况下，如图4(d)所示，随着光纤长度的增加，信号光的功率继续增加，在HNLF2的输出端达到1.98W，同时如图4(a)和(b)所示，两个泵浦光的功率减少到接近0，泵浦光向信号光的能量转换效率显著提高。同时，在信号光的增益随光纤长度变化的图5中看出，相比较于没有相移光栅引入，信号光的最大增益提高了4.3dB，输出增益提高了18.1dB。简言之，相移光栅的引入显著提高了光纤参量放大器的增益。 Then the four optical waves after phase mismatch compensation continue to be parametrically amplified through the second section of highly nonlinear optical fiber, which realizes further amplification of signal optical power and improves the gain of the optical fiber parametric amplifier. Among them, the high nonlinear optical fibers HNLF2 and HNLF1 have the same optical fiber parameters except for the different optical fiber lengths. In this scheme, the length of HNLF2 is 36m. Figure 4 illustrates the relationship between the power of pump light 1, pump light 2, idler light and signal light as a function of the length of the two sections of highly nonlinear optical fibers when phase-shifting gratings are introduced or not. It can be seen that after the two pump lights with an input power of 2W and the signal light with an input power of 1mW pass through HNLF1, through the parametric amplification process, the energy of the two pump lights will be transferred to the signal light and the idler light. The power of the two pump lights at a length of 60m is reduced to 1.24W at the lowest, and the power of the signal light is amplified to 0.75W at the maximum. If there is no phase shift grating, with the increase of the fiber length, the previous pump light will increase to the signal light. The direction of energy transfer changes, and then the power of the signal light does not continue to amplify, but continues to decrease to close to 0. At the same time, the power of the pump light gradually increases to close to the input power. Obviously, the amplification effect on the signal light at this time little. But if the phase shift grating is introduced, at the fiber length of 60m, because of the reflection of the phase shift grating on the idler light, as shown in Figure 4(c), the power of the idler light is reduced from 0.75W to 0.22W, and a π phase shift, which in turn compensates for the phase mismatch in the parametric process. In this case, as shown in Figure 4(d), as the fiber length increases, the power of the signal light continues to increase, reaching 1.98W at the output of HNLF2, as shown in Figure 4(a) and (b) , the power of the two pump lights is reduced to close to 0, and the energy conversion efficiency of the pump light to the signal light is significantly improved. At the same time, it can be seen from Figure 5 that the gain of signal light varies with the length of the fiber. Compared with the introduction of no phase shift grating, the maximum gain of signal light is increased by 4.3dB, and the output gain is increased by 18.1dB. In short, the introduction of phase-shifting gratings significantly increases the gain of fiber parametric amplifiers. the

另一方面，在考虑相移光栅与高非线性光纤的连接损耗时，引入相移光栅对光纤参量放大器增益的影响，在图6中看到，通过相移光栅的引入，即使每个连接点处的插入损耗为1dB，信号光的增益仍然提高了1.7dB，而一般情况下，每个连接点处的插入损耗少于0.5dB。很显然在实际系统中，相移光栅的引入仍然可以显著提高光纤参量放大器的增益。 On the other hand, when considering the connection loss between the phase shift grating and the highly nonlinear fiber, the influence of introducing the phase shift grating on the gain of the fiber parametric amplifier can be seen in Fig. 6, through the introduction of the phase shift grating, even if each connection point The insertion loss at each connection point is 1dB, and the gain of the signal light is still increased by 1.7dB, but in general, the insertion loss at each connection point is less than 0.5dB. Obviously, in the actual system, the introduction of the phase shift grating can still significantly improve the gain of the fiber parametric amplifier. the

综合以上陈述，本发明具有如下特征：1).在光纤参量放大系统的两段高非线性光纤中引入了相移光栅；2).利用相移光栅对闲频光滤波和移相，补偿了光纤参量过程中的相位失配，提高光纤参量放大器的增益；3).通过选择相移光栅的反射率和相移，在可调谐范围内，实现不同条件下光纤参量放大器增益的提高。有利于优化光纤参量放大器的特性，为密集波分复用光通信系统的全光放大技术提供新的方案。 In summary, the present invention has the following features: 1). Phase-shift gratings are introduced in two sections of highly nonlinear optical fibers of the optical fiber parametric amplification system; The phase mismatch in the fiber parametric process improves the gain of the fiber parametric amplifier; 3). By selecting the reflectivity and phase shift of the phase shift grating, within the tunable range, the gain of the fiber parametric amplifier is improved under different conditions. It is beneficial to optimize the characteristics of the fiber parametric amplifier, and provides a new solution for the all-optical amplification technology of the dense wavelength division multiplexing optical communication system. the

以上所陈述的仅仅是本发明方案及装置的优选实施方式，应当指出，在不脱离本发明方案及装置实质的前提下，在实际实施中可以做出若干更改(比如改变泵浦光和信号光的输入功率和波长时，改变相移光栅的反射率和相移时，改变高非线性光纤的非线性系数和光纤长度时)也应包含在本发明的保护范围以内。 What is stated above is only the preferred implementation mode of the scheme and the device of the present invention. It should be pointed out that without departing from the essence of the scheme and the device of the present invention, some changes can be made in actual implementation (such as changing the pumping light and the signal light When changing the reflectivity and phase shift of the phase shift grating, changing the nonlinear coefficient and fiber length of the highly nonlinear optical fiber) should also be included in the protection scope of the present invention. the

Claims

1. The scheme and device for improving the gain of fiber parametric amplifier by using phase-shift grating, which consists of external cavity laser ECL, phase modulator PM, erbium-doped fiber amplifier EDFA, polarization controller PC, coupler OC, phase-shift grating PS-FBG, high It consists of nonlinear optical fiber HNLF and optical spectrum analyzer OSA, which is characterized in that the pump light Pump1 generated by the external cavity laser ECL1 and the pump light Pump2 generated by the external cavity laser ECL2 are respectively modulated by phase modulators PM1 and PM2, and the erbium-doped fiber amplifier After EDFA1 and EDFA2 are amplified, and polarization controllers PC1 and PC2 adjust their polarization states, they are coupled through coupler OC1 and coupled with the signal light Signal generated by external cavity laser ECL3 adjusted by polarization controller PC3 into coupler OC2, and then the two A pump light and a signal light enter the highly nonlinear fiber HNLF1 at the same time, through the parametric process in the fiber, the idler light is generated and the signal light is amplified, and then the four light waves enter the phase shift grating PS-FBG at the same time, and pass through the phase shift grating Phase matching is achieved by partial filtering and phase shifting of the idler light, and then re-amplification of the signal light is achieved after entering the high nonlinear fiber HNLF2, and the corresponding power changes are measured by spectrum analyzers OSA1 and OSA2. The phase shift grating adopted in the invention performs phase mismatch compensation to realize the improvement of the gain of the optical fiber parametric amplifier.

2. the scheme and the device that adopt phase-shift grating to improve fiber parametric amplifier gain according to claim 1, it is characterized in that, introduce phase-shift grating between two sections of highly nonlinear optical fibers as filter and phase shifter to idler light Reflection and phase shift are generated to compensate the phase mismatch in the fiber parametric process. And by selecting the reflectivity and phase shift of the phase-shifting grating, within the tunable range, the gain of the fiber parametric amplifier under different conditions can be improved.

3. the scheme and the device that adopt phase-shift grating to improve fiber parametric amplifier gain according to claim 1, it is characterized in that, the raising of this fiber parametric amplifier gain is equally applicable to pumping light wavelength and optical fiber zero dispersion wavelength interval being a relative over a wide wavelength range.