CN-224217895-U - Multi-wavelength random fiber laser based on four-port circulator and Brillouin-Rayleigh scattering

CN224217895UCN 224217895 UCN224217895 UCN 224217895UCN-224217895-U

Abstract

The utility model belongs to the technical field of fiber lasers, and relates to a multi-wavelength random fiber laser based on a four-port circulator and Brillouin-Rayleigh scattering, which is a closed-loop random fiber laser, and comprises a four-port circulator, wherein a first port of the four-port circulator is connected with a seed laser, a second port of the four-port circulator is connected with a Brillouin gain fiber, a third port of the four-port circulator is connected with a random Rayleigh scattering fiber, a fourth port of the four-port circulator is connected with a fiber coupler, an erbium-doped fiber and a wavelength division multiplexer are connected between the Brillouin gain fiber and the fiber coupler, and a pumping port of the wavelength division multiplexer is connected with an output port of a 980nm laser. The utility model combines the Rayleigh scattering of the random Rayleigh scattering fiber and the gain amplification of the erbium-doped fiber through the Brillouin scattering of the Brillouin gain fiber, the high-efficiency stable multi-wavelength output is realized, the output wavelength number is adjustable, the stability is high, and the high-precision optical fiber sensor is suitable for a high-precision optical fiber sensing and dense wavelength division multiplexing system.

Inventors

HAO YUNQI
MIAO MIAO
CHENG SHIQI
LI FUTIAN
HE WEIHAO
ZHAI FENGXIAO
YANG KUN

Assignees

郑州轻工业大学

Dates

Publication Date: 20260508
Application Date: 20250617

Claims (9)

1. A multi-wavelength random fiber laser based on a four-port circulator and Brillouin-Rayleigh scattering is characterized by comprising a closed-loop random fiber laser, wherein the closed-loop random fiber laser comprises a four-port circulator (2), a first port of the four-port circulator (2) is connected with a seed laser (1), a second port of the four-port circulator is connected with a Brillouin gain fiber (3), a third port of the four-port circulator is connected with a random Rayleigh scattering fiber (8), a fourth port of the four-port circulator is connected with a fiber coupler (7), an erbium-doped fiber (4) and a wavelength division multiplexer (5) are connected between the Brillouin gain fiber (3) and the fiber coupler (7), and a pumping port of the wavelength division multiplexer (5) is connected with an output port of a 980nm laser (6).
2. The multi-wavelength random fiber laser based on the four-port circulator and the Brillouin-Rayleigh scattering, as claimed in claim 1, wherein the center wavelength of the seed laser (1) is in 1550nm band, and an initial pumping optical signal is provided.
3. The multi-wavelength random fiber laser based on the four-port circulator and the Brillouin-Rayleigh scattering according to claim 1, wherein the four-port circulator (2) controls unidirectional transmission of optical signals.
4. A multi-wavelength random fiber laser based on a four-port circulator and Brillouin-Rayleigh scattering according to claim 1, wherein the second port of the four-port circulator (2) is connected with the first port of the Brillouin gain fiber (3), the second port of the Brillouin gain fiber (3) is connected with the first port of the erbium-doped fiber (4), and the second port of the erbium-doped fiber (4) is connected with the common port of the wavelength division multiplexer (5).
5. The multi-wavelength random fiber laser based on four-port circulator and Brillouin-Rayleigh scattering according to claim 1, wherein the fiber coupler (7) is a 1:9 fiber coupler, and has an input port, 90% of main output ports and 10% of output and monitoring ports.
6. The multi-wavelength random fiber laser based on four-port circulator and Brillouin-Rayleigh scattering according to claim 5, wherein the pump light port of the wavelength division multiplexer (5) is connected with the first port of the 980nm laser (6), the signal light port of the wavelength division multiplexer (5) is connected with 90% of the main output port of the fiber coupler (7), and the input port of the fiber coupler (7) is connected with the fourth port of the four-port circulator (2).
7. The multi-wavelength random fiber laser based on four-port circulator and Brillouin-Rayleigh scattering according to claim 6, wherein the 980nm laser (6) is a pumping light source.
8. The multi-wavelength random fiber laser based on the four-port circulator and the Brillouin-Rayleigh scattering according to claim 1, wherein the other end of the random Rayleigh scattering fiber (8) is cut into an angle of 8 degrees.
9. The multi-wavelength random fiber laser based on four-port circulator and Brillouin-Rayleigh scattering according to claim 8, wherein the third port of the four-port circulator (2) is connected with the first port of the random Rayleigh scattering fiber (8), and the second port of the random Rayleigh scattering fiber (8) is connected with the 8-degree angle fiber end face (9).

Description

Multi-wavelength random fiber laser based on four-port circulator and Brillouin-Rayleigh scattering Technical Field The utility model belongs to the technical field of fiber lasers, relates to a multi-wavelength random fiber laser based on a four-port circulator and Brillouin-Rayleigh scattering, and particularly relates to a closed-loop random laser based on a four-port circulator, a seed laser, a long-distance Brillouin gain fiber, a random Rayleigh scattering fiber and an erbium-doped fiber, and the efficient and stable random laser output is realized through the synergistic effect of stimulated Brillouin scattering and random Rayleigh scattering. Background The random fiber laser has important application in the fields of fiber sensing, communication, spectrum analysis and the like because of the advantages of no fixed cavity structure, low coherence, simple device and the like. 2010, university of aston, uk Turitsyn et al 【Turitsyn S K,Babin SA,El-TaherAE,et al.Random distributedfeedback fibre laser[J].Nature photonics,2010,4(4):231-235.】 The random laser with all-fiber structure using one-dimensional fiber as random medium is realized for the first time, and then the random laser is widely studied. Random laser provides random distributed feedback by means of Rayleigh scattering in long-distance single-mode fiber, rayleigh enhancement fiber or random grating, amplification gain is provided by means of erbium-doped fiber and the like, laser wavelength is selected by means of Bragg fiber grating filter or comb filter, linear full-open cavity or annular half-open cavity is built, random laser output is achieved, but pumping efficiency is low and stability is insufficient. In recent years, stimulated brillouin scattering has been introduced into random laser systems due to its high gain characteristics, and the combination of random rayleigh scattering can significantly enhance laser conversion efficiency and expand the output wavelength range. In prior literature 【PangM,Xie S,Bao X,et al.Rayleigh scattering-assisted narrow linewidth Brillouin lasing in cascaded fiber.Optics letters,2012,37(15):3129-3131.】, random laser output with a narrow linewidth of 3.4kHz is realized by three different spliced fibers, the amplification of stokes light by a middle high brillouin gain fiber pair and the enhancement of rayleigh scattering by two side fibers. The patent [ 2021, guangdong university of industry ] proposes a low-noise brillouin random fiber laser, CN113097845A, in which brillouin scattered light is generated by using a high-germanium-doped fiber, and a femtosecond laser is used for writing a random grating as a random feedback laser structure, so that the cavity length of the brillouin random fiber laser is shortened by more than three orders of magnitude. In the prior literature 【Guo T,Zhang A,Pan H,et al.Tunable multi-wavelength SBS Q-switched random fiber laser based on SMF[J].Applied Physics B,2022,128(5):99.】, a tunable multi-wavelength stimulated Brillouin scattering Q-switched random fiber laser with a half-open cavity structure is proposed, and 1-18-order laser output is realized by adjusting pumping power and tunable laser source power. In the prior literature 【PangY,Ma S,Zhao X,et al.Single-longitudinal-mode short-cavity Brillouin random fiber laser via frequency auto-tracking with unpumped-EDF Sagnac loop[J].Infrared Physics&Technology,2022,127:104461.】, it is proposed to use a non-pumping erbium-doped fiber Sagnac loop as a filter structure, and combine the brillouin gain in the nonlinear fiber and the rayleigh scattering feedback in the single-mode fiber to obtain a narrow linewidth random laser output. In prior literature 【Xu L,WangY,Dai S,et al.Single-longitudinal-mode Brillouin random fiber laser with high linewidth-compression ratio and laser efficiency based on distributed intrinsic feedback mechanism[J].Optics&Laser Technology,2022,156:108471.】, it is proposed to obtain random laser output with high linewidth compression ratio and conversion efficiency by using a distributed intrinsic feedback mechanism structure of an enhanced rayleigh scattering optical fiber and brillouin gain of a small core optical fiber. In the above prior document, the random laser cavity contains two three-port circulators, one circulator injects seed light into the brillouin gain fiber, and the other circulator introduces reverse stimulated brillouin scattered light into the random rayleigh scattering fiber. The more optical devices in the optical path increase the complexity of the system, and the uncontrollable factors are introduced to reduce the output performance and quality of the laser beam. Disclosure of utility model The utility model aims to provide a random fiber laser based on a four-port circulator and a Brillouin-Rayleigh scattering mechanism, and aims to realize high-stability random Brillouin laser output by utilizing seed laser to excite Brillouin scattering and combining random Rayleigh scatter