CN215452036U

CN215452036U - Novel narrow-linewidth high-power optical fiber laser generation device based on dispersion management

Info

Publication number: CN215452036U
Application number: CN202120922617.4U
Authority: CN
Inventors: 张璟璞; 丁亚茜; 邢美术
Original assignee: Shanghai Transmission Line Research Institute No 23 Research Institute Of China Electronics Technology Group Corp
Current assignee: Shanghai Transmission Line Research Institute No 23 Research Institute Of China Electronics Technology Group Corp
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2022-01-07
Anticipated expiration: 2031-04-30

Abstract

The utility model belongs to the technical field of fiber laser, and particularly relates to a novel narrow-linewidth high-power fiber laser generating device based on dispersion management, which mainly comprises a super-fluorescence source seed, a narrow-linewidth filtering module, a dispersion management module and a laser power amplification module, wherein the modules are sequentially connected by using optical fibers, and the phase relation among sub-wavelengths in a traditional narrow-linewidth seed laser signal is changed by a dispersion management method, so that the intensity of nonlinear effect in a power amplification stage is weakened, the speed of spectrum broadening in the laser power amplification stage is inhibited, and high-power laser output with narrow linewidth is obtained.

Description

Novel narrow-linewidth high-power optical fiber laser generation device based on dispersion management

Technical Field

The utility model belongs to the technical field of fiber laser, and particularly relates to a novel narrow-linewidth high-power fiber laser generating device based on dispersion management.

Background

The narrow-linewidth high-power optical fiber laser has important application in the fields of light beam synthesis, laser frequency doubling, laser communication and the like. For a general narrow linewidth seed source, in the laser power amplification process, the output spectral width is widened, and the narrow linewidth characteristic cannot be maintained in the high-power output process. The researchers have proposed a single-frequency optical phase modulation method, which realizes spectrum broadening by phase modulation of a single-frequency seed source, and then performs power amplification on the broadened signal. The method can obtain high-power laser output while keeping the laser linewidth at a narrow level. However, this solution requires a plurality of rf signal sources, electro-optic phase modulators and corresponding circuit control modules, and has a complex structure, high cost and insufficient reliability. Therefore, the development of a novel narrow-linewidth high-power fiber laser system with simple structure, stable performance and low cost becomes an important research direction.

SUMMERY OF THE UTILITY MODEL

Compared with the prior technical scheme, the novel narrow-linewidth high-power optical fiber laser generation device has the advantages of full optical fiber, simple structure and low cost, and lays a foundation for large-scale application of narrow-linewidth high-power lasers.

The specific technical scheme is as follows:

a novel narrow linewidth high-power optical fiber laser generation device based on dispersion management is characterized in that: the laser generating device mainly comprises a super-fluorescence source seed 101, wherein the super-fluorescence source seed 101 is used for generating a laser signal;

the narrow linewidth filtering module 102, the narrow linewidth laser with specific central wavelength is obtained by the laser signal through the narrow linewidth filtering module 102;

the dispersion management module 103 is used for changing the phase of different wavelengths under the influence of dispersion effect in the bandwidth of the laser signal;

the laser power amplification module 104 is used for weakening the intensity of the nonlinear effect, inhibiting the speed of spectrum broadening, and improving the laser power.

The super-fluorescent source seed 101, the narrow linewidth filtering module 102, the dispersion management module 103 and the laser power amplification module 104 are connected in sequence by using optical fibers.

Further, the super-fluorescent source seed 101 is composed of a gain fiber 201, a pump signal combiner 202 and a semiconductor pump source 203, and pump light output by the semiconductor pump source 203 is injected into the gain fiber 201 through the pump signal combiner 202.

Further, the gain fiber 201 is an ytterbium-doped gain fiber.

Further, the end face of the gain fiber 201 is chamfered.

Further, the narrow linewidth filtering module 102 is composed of a fiber grating 204, or a volume bragg grating, or a surface grating, or a chirped fiber grating 209.

Further, the dispersion management module 103 is composed of a passive fiber 206 or a chirped fiber grating 209 and a fiber circulator 205.

Further, the passive fiber 206 is a G652D fiber that is not less than 4km long.

Further, the laser power amplification module 104 is formed by one or more optical fiber power amplification structures as required, each optical fiber power amplification structure includes a semiconductor pump source 203, a pump signal combiner 202, a gain fiber 201, and a cladding light stripper 207, the semiconductor pump source 03, the pump signal combiner 202, the gain fiber 201, and the cladding light stripper 207 are connected by optical fibers in sequence, and an optical fiber isolator 208 is welded between the optical fiber power amplification structures.

The utility model has the following beneficial effects:

the utility model provides a novel narrow-linewidth high-power optical fiber laser generating device based on dispersion management, which changes the phase relation among all sub-wavelengths in a traditional narrow-linewidth seed laser signal, thereby weakening the intensity of nonlinear effect in a power amplification stage, inhibiting the speed of spectrum broadening in the laser power amplification stage and obtaining the high-power laser output with narrower linewidth. The utility model has the advantages of full optical fiber, simple structure and low cost, and lays a foundation for the large-scale application of narrow-linewidth high-power lasers.

Drawings

FIG. 1 is a block diagram of a novel narrow linewidth high power fiber laser device;

FIG. 2 is a schematic diagram of a laser generating device according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a laser generating apparatus according to an embodiment of the present invention.

Description of reference numerals:

101. a super-fluorescent source seed; 102. a narrow linewidth filtering module; 103. a dispersion management module; 104. a laser power amplification module; 201. a gain fiber; 202. a pump signal combiner; 203. a semiconductor pump source; 204. a fiber grating; 205. a fiber optic circulator; 206. a passive optical fiber; 207. a cladding light stripper; 208. a fiber isolator; 209. chirped fiber grating.

Detailed Description

In order to make the embodiments of the present invention more clear, the present invention will be explained in detail below with reference to the accompanying drawings and examples. The specific embodiments described herein are merely illustrative of the utility model and do not limit the scope of the utility model as claimed.

Fig. 1 is a schematic block diagram of a narrow-linewidth high-power fiber laser generation device based on dispersion management according to the present invention, which mainly comprises four modules: the system comprises a super-fluorescence source seed 101, a narrow linewidth filtering module 102, a dispersion management module 103 and a laser power amplification module 104. The modules are connected in sequence through optical fibers. According to different implementation cases, the modules are formed in different ways.

The super-fluorescent light source seeds 101 generate broadband laser signals, and narrow linewidth lasers with specific central wavelengths are obtained after passing through the narrow linewidth filtering module 102. After passing through the dispersion management module 103, the phase of different wavelengths within the laser signal bandwidth changes differently under the influence of the dispersion effect, so that in the subsequent laser power amplification module 104, the intensity of the nonlinear effect is weakened, the speed of spectrum broadening is suppressed, and narrow-linewidth high-power laser is generated.

The first embodiment is as follows:

fig. 2 is a schematic structural diagram of a laser generator according to this embodiment.

The super-fluorescent source seed 101 in this embodiment mainly includes a gain fiber 201, a pump signal combiner 202, and a semiconductor pump source 203. The 976nm pump light output by the semiconductor pump source 203 is injected into the gain fiber 201 through the pump signal combiner 202. In this embodiment, the gain fiber 201 is an ytterbium-doped gain fiber, and the end face of the gain fiber 201 is chamfered to reduce the ratio of the return light, so that the gain fiber 201 operates in a spontaneous radiation state and outputs incoherent light with a wide spectrum in a range of 1030nm to 1090 nm.

The narrow linewidth filtering module 102 in this embodiment mainly includes an optical fiber circulator 205 and an optical fiber grating 204, the wide spectrum laser output by the seed source enters from a port 1 of the optical fiber circulator 205, and the central wavelength of the optical fiber grating 204 can be tuned in a sub-nanometer order through a change in temperature or stress, so as to obtain a narrow linewidth seed source with an adjustable central wavelength. The spectral filtering element used by the narrow linewidth filtering module 102 may also be a fiber grating 204, a volume bragg grating, a surface grating, or other optical devices that can implement the narrow linewidth filtering function.

The dispersion management module 103 of this embodiment is mainly composed of a passive fiber 206, in this embodiment, the passive fiber 206 is a 4km long G652D fiber, and the dispersion effect required by the present invention is achieved by using the dispersion effect of the passive fiber 206. Due to the nonlinear effect existing in the passive optical fiber 206, the spectral width of the laser output by the dispersion management module 103 is broadened to 0.12 nm.

The laser power amplification module 104 in this embodiment mainly includes a semiconductor pump source 203, a pump signal combiner 202, a gain fiber 201, a cladding light stripper 207, and a fiber isolator 208. In the embodiment, a four-stage power amplification structure is adopted, and the output power is gradually increased to 1 kW. The cladding light stripper 207 is used for stripping unabsorbed residual pumping light and high-order mode laser signals leaked into the cladding, and the optical fiber isolator 208 is used for protecting the optical devices of the previous stage from being damaged by backward return light of the next stage. After four-stage power amplification, the output laser power reaches 1kW, and the spectral line width is 0.16 nm.

Example two:

as described in the first embodiment, a long-haul passive fiber 206 is used as the dispersion management module 103. In this example, the narrow linewidth filtering module 102 and the dispersion management module 103 are constructed in another form.

The specific structure of the laser generating device is shown in fig. 3. The structure and principle of the super-fluorescent source seed 101 are the same as those of the first embodiment, and are not described herein again.

The narrow linewidth filtering module 102 in this embodiment adopts the optical fiber circulator 205 and the chirped fiber grating 209, the refractive index modulation period of the chirped fiber grating 209 changes linearly or nonlinearly in the optical fiber axial direction, the insertion loss is small, the dispersion compensation amount is large, and the dispersion generated by an optical fiber with a length of several centimeters can be compensated for over a hundred kilometers. The chirped fiber grating 209 is used as a filter device, and the functions of the narrow linewidth filter module 102 and the dispersion management module 103 can be simultaneously completed. Two narrow linewidth filtering modules 102 composed of the optical fiber circulator 205 and the chirped fiber grating 209 are cascaded to obtain signal light with high spectral signal-to-noise ratio, and the laser power is increased to 1kW by a four-stage power amplifier with the same structure as that in the first embodiment.

The present invention is not limited to the above embodiments, but should be defined by the scope of the appended claims.

Claims

1. A novel narrow linewidth high-power optical fiber laser generation device based on dispersion management is characterized in that: the laser generating device mainly comprises a super-fluorescence source seed (101), wherein the super-fluorescence source seed (101) is used for generating a laser signal;

the narrow linewidth filtering module (102), the laser signal gets the narrow linewidth laser of the specific central wavelength through the narrow linewidth filtering module (102);

a dispersion management module (103), the dispersion management module (103) being configured to change the phase of different wavelengths within the bandwidth of the laser signal under the influence of a dispersion effect;

the laser power amplification module (104), the laser power amplification module (104) is used for weakening the intensity of the nonlinear effect, inhibiting the speed of spectrum broadening, and improving the laser power;

the super-fluorescent light source seeds (101), the narrow linewidth filtering module (102), the dispersion management module (103) and the laser power amplification module (104) are connected in sequence through optical fibers.

2. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 1, wherein: the super-fluorescence source seed (101) is composed of a gain fiber (201), a pumping signal beam combiner (202) and a semiconductor pumping source (203), and pumping light output by the semiconductor pumping source (203) is injected into the gain fiber (201) through the pumping signal beam combiner (202).

3. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 2, wherein: the gain fiber (201) is an ytterbium-doped gain fiber.

4. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 2, wherein: the end face of the gain fiber (201) is processed by beveling.

5. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 1, wherein: the narrow linewidth filtering module (102) is composed of a fiber grating (204), a volume Bragg grating, a surface grating or a chirped fiber grating (209).

6. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 1, wherein: the dispersion management module (103) is composed of a passive fiber (206) or a chirped fiber grating (209) and a fiber circulator (205).

7. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 6, wherein: the passive optical fiber (206) is a G652D optical fiber not less than 4km long.

8. The novel narrow-linewidth high-power fiber laser generating device based on dispersion management according to claim 1, wherein: the laser power amplification module (104) is composed of one or more optical fiber power amplification structures as required, each optical fiber power amplification structure comprises a semiconductor pump source (203), a pump signal combiner (202), a gain optical fiber (201) and a cladding light stripper (207), the semiconductor pump source (203), the pump signal combiner (202), the gain optical fiber (201) and the cladding light stripper (207) are sequentially connected through optical fibers, and an optical fiber isolator (208) is welded between each optical fiber power amplification structure.