Dual-wavelength fiber laser for regulating soliton explosion

Abstract

The invention belongs to the technical field of lasers, and discloses a dual-wavelength fiber laser for regulating soliton explosion. The optical fiber laser comprises a laser pumping source, a wavelength division multiplexer, an erbium-doped gain optical fiber, a dispersion compensation optical fiber, a polarization independent isolator, an output coupler, a polarization controller and a saturable absorber mode locking device based on a carbon black / graphene oxide composite material, which are sequentially connected through a single-mode optical fiber. By adjusting the pumping power and the polarization controller, the dual-period coexistence phenomenon of explosion caused by soliton collision and soliton spontaneous explosion is successfully achieved, and the period of spontaneous explosion is adjustable. According to the invention, the precise control capability of the extreme non-linear phenomenon in the fiber laser is obviously improved, and the performance and stability of the fiber laser are effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of optical fiber lasers, and in particular to a dual-wavelength optical fiber laser for regulating soliton explosion. Background Art

[0002] Solitons are an important phenomenon in nonlinear optics. Their propagation in optical fibers is characterized by a precise balance between dispersion and nonlinear effects. In recent years, soliton explosions, an extreme dynamic phenomenon, have attracted widespread attention. Soliton explosions not only reveal the complex nonlinear dynamics of optical fibers, but also have potential application value in optical communications, ultrafast laser technology, and nonlinear optics research.

[0003] However, there is currently a lack of effective means to regulate the periodic explosion behavior of dual-wavelength solitons, making it difficult to achieve precise control of their periodic and dynamic characteristics. This limits their further application in the fields of high-precision fiber-optic communications and ultrafast light sources. Therefore, there is an urgent need for a fiber laser that can regulate the periodic explosion of dual-wavelength solitons to break through the bottleneck of existing technologies. Summary of the invention

[0004] In order to solve the above-mentioned deficiencies and shortcomings of the prior art, the present invention provides a dual-wavelength fiber laser for regulating soliton explosion.

[0005] To achieve the above-mentioned purpose, a dual-wavelength fiber laser for regulating soliton explosion, specifically, includes a laser pump source, a wavelength division multiplexer, an erbium-doped gain fiber, a dispersion compensation fiber, a polarization-independent isolator, an output coupler, a polarization controller and a carbon black / graphene oxide composite saturable absorber mode-locking device.

[0006] Preferably, the laser pump uses 976nm band laser, which has strong stability and adjustable power, and is the key to achieving dual-wavelength explosion.

[0007] Preferably, the wavelength division multiplexer comprises a first input end 21 and a second input end 22, which functions to couple the 976nm pump light with the C-band light wave and input them into the resonant cavity.

[0008] Preferably, the erbium-doped gain fiber is 0.4 m long, and its unique energy level structure and excitation form are conducive to the gain of C-band light waves and broadband light wave transmission.

[0009] Preferably, the dispersion compensation optical fiber has a length of 0.8 m, and is used to compensate for the dispersion characteristics in the cavity, thereby achieving positive dispersion dual-wavelength mode locking.

[0010] Preferably, the single-mode optical fiber has a total length of 6.1 m and is used to transmit C-band light waves.

[0011] Preferably, the polarization controller can adjust the polarization state of light, thereby changing the balance between nonlinear effects, dispersion effects, gain and loss in the cavity, thereby triggering explosions of different periods in the dual-wavelength laser.

[0012] Preferably, the carbon black / graphene oxide composite saturable absorber locking device is obtained by mixing a carbon black solution and a graphene oxide solution by a hydrothermal method, adding the mixture to a polyvinyl alcohol solution and stirring for one hour, then placing the mixed solution in a polytetrafluoroethylene culture dish and drying it in a drying oven at 60 degrees Celsius for 6 hours.

[0013] Preferably, the output coupler comprises a 50% output end 81 and a 50% output end 82, the laser at one end continues to pass into the optical path to form a closed-loop resonant cavity, and the other end outputs outside the cavity for observing the output characteristics of the laser pulse.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The present invention proposes a dual-wavelength fiber laser for regulating soliton explosion, which has the advantage of realizing precise regulation of dual-period soliton explosion phenomenon. By adjusting the pump power and polarization controller, the explosion caused by soliton collision and the spontaneous soliton explosion can be realized simultaneously, and the period of the spontaneous soliton explosion is adjustable. The laser greatly improves the stable control of the soliton dynamic behavior and enhances the output stability and dynamic regulation ability of the laser by optimizing the intracavity structure, including dispersion compensation fiber and saturable absorber locking device based on carbon black / graphene oxide composite material. It is suitable for high-precision fiber communication, ultrafast light source development and nonlinear optical research, breaking through the bottleneck of the existing technology in dual-period soliton explosion regulation, and providing a new solution for fiber laser technology and nonlinear dynamic research. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 (a) is a schematic diagram of the structure of a dual-wavelength fiber laser for regulating soliton explosion of the present invention, 1 is a laser pump source, 2 is a wavelength division multiplexer, 3 is an erbium-doped gain fiber, 4 is a dispersion compensation fiber, 5 is a polarization-independent isolator, 6 is a polarization controller, 7 is a carbon black / graphene oxide composite saturable absorber mode-locking device, and 8 is an output coupler. Figure 1 (b) is the spectrum of positive dispersion dual-wavelength mode locking.

[0018] Figure 2 This is an oscilloscope image of a dual-wavelength soliton dual-period explosion, where the explosion occurs at the high peak. Figure 2 The explosion period of (a) is 28-130, Figure 2 (b) has an explosion period of 28-150, Figure 2 The explosion period of (c) is 28-211.

[0019] Figure 3 This is the dynamic evolution process of dual-wavelength soliton explosions with different periods. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Example

[0022] The present invention aims to change the balance between nonlinear effect, dispersion effect, gain and loss by adjusting the polarization controller of the fiber laser, thereby controlling the double-cycle explosion phenomenon in the dual-wavelength fiber laser and optimizing the performance of the fiber laser.

[0023] Figure 1 (a) is a schematic diagram of the structure and results of a dual-wavelength fiber laser for regulating soliton explosion provided by the present invention. Figure 1 As shown in (a), the laser pump source 1, wavelength division multiplexer 2, erbium-doped gain fiber 3, dispersion compensation fiber 4, polarization-independent isolator 5, polarization controller 6, carbon black / graphene oxide composite saturable absorber 7, and output coupler 8 are connected in sequence to form a ring laser resonator. Figure 1 (b) is the spectrum of dual-wavelength dissipative solitons that appear when the polarization controller is adjusted with a pump power of 200mW.

[0024] The laser pump 1 uses 976nm band laser, which has strong stability and adjustable power, and is the key to achieving dual-wavelength explosion.

[0025] The wavelength division multiplexer 2 includes a first input end 21 and a second input end 22, and its function is to couple the 976nm pump light with the C-band light wave and input them into the resonant cavity.

[0026] The erbium-doped gain optical fiber 3 has a length of 0.4 m, and its unique energy level structure and excitation form are conducive to the gain of C-band light waves and the transmission of wide-band light waves.

[0027] The dispersion compensation optical fiber 4 has a length of 0.8 m and is used to compensate for the dispersion characteristics in the cavity, thereby achieving positive dispersion dual-wavelength mode locking.

[0028] The polarization-independent isolator 5 prevents the light beam from flowing back.

[0029] The polarization controller 6 is used to adjust the polarization state of light, thereby changing the balance between nonlinear effects, dispersion effects, gain and loss in the cavity, thereby triggering explosions of different periods in the dual-wavelength laser.

[0030] The carbon black / graphene oxide composite saturable absorber 7 is obtained by mixing a carbon black solution and a graphene oxide solution by a hydrothermal method, adding the mixture to a polyvinyl alcohol solution and stirring for one hour, then placing the mixed solution in a polytetrafluoroethylene culture dish and drying it in a drying oven at 60 degrees Celsius for 6 hours.

[0031] The output coupler 8 comprises a 50% output end 81 and a 50% output end 82. The laser at one end continues to pass into the optical path to form a closed-loop resonant cavity, and the other end outputs outside the cavity to observe the output characteristics of the laser pulse.

[0032] As a specific example, Figure 2 The different periodic explosion phenomena of dual-wavelength solitons under different polarizations are shown. Including explosions caused by the collision of two solitons and spontaneous explosions. The collision period can be expressed by the formula: Calculated. Where L is the cavity length, D is the dispersion parameter, is the difference between the central wavelengths of the dual-wavelength solitons, and n is the refractive index of the optical fiber.

[0033] Figure 3 The dynamic evolution diagram corresponding to different periodic explosions is shown. It can be seen from the diagram that the explosion caused by collision is different from the spontaneous explosion. By adjusting the polarization controller, the period of the explosion can be changed.

[0034] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A dual-wavelength fiber laser for regulating soliton explosion, characterized in that: The invention comprises a laser pump source, a first input end 21 of a wavelength division multiplexer, an erbium-doped gain fiber, a dispersion compensation fiber, a polarization-independent isolator, an output coupler, a polarization controller, a saturable absorber mode-locked device based on a carbon black / graphene oxide composite material, and a second input end 22 of the wavelength division multiplexer, and they are connected in sequence through a single-mode optical fiber to form a ring laser resonant cavity.

2. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The laser pump adopts 976nm band laser; the length of the erbium-doped gain fiber is 0.4m; the length of the dispersion compensation fiber is 0.8m; the total length of the single-mode fiber is 6.1m; the output ratio of the output coupler is 5:5; the carbon black / graphene oxide composite saturable absorber mode-locking device consists of two optical fiber connectors and a carbon black / graphene oxide composite saturable absorber film in the middle.

3. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The laser pump source has strong stability and adjustable power, and is the key to realizing dual-wavelength soliton explosion.

4. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The wavelength division multiplexer comprises a first input end 21 and a second input end 22, and functions to couple the 976nm pump light with the C-band light wave and input the light into the resonant cavity.

5. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The erbium-doped gain optical fiber can amplify optical signals of different wavelengths, thereby enhancing the signal strength of multiple channels, so that it can maintain high quality and low loss during long-distance transmission.

6. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The dispersion compensating optical fiber is used to adjust the dispersion characteristics in the cavity so as to achieve positive dispersion dual-wavelength mode locking.

7. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The polarization-independent isolator prevents the light beam from flowing back.

8. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The output coupler is used to disperse the laser in the optical path into two pulses, one laser beam continues to pass into the optical path to form a closed-loop resonant cavity, and the other laser beam is output outside the cavity to observe the output characteristics of the laser pulse.

9. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The polarization controller can adjust the polarization state of light to change the balance between nonlinear effects, dispersion effects, gain and loss in the cavity, thereby triggering explosions of different periods in the dual-wavelength laser.

10. A dual-wavelength fiber laser for regulating soliton explosion according to claim 1, characterized in that: The carbon black / graphene oxide composite saturable absorber mode-locking device is beneficial to maintaining the stability of pulse characteristics and reducing nonlinear distortion caused by heat.

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