A multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping

Abstract

This invention discloses a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping, comprising a 1.5μm Brillouin pump, a 1.45μm tunable broadband Raman pump, a wavelength division multiplexer (WDM) I, and a passive fiber. The 1.45μm tunable broadband Raman pump includes a wavelength-tunable cascaded random Raman fiber laser, a WDM II, and a single-mode fiber I. The wavelength-tunable cascaded random Raman fiber laser is injected into the single-mode fiber I through the WDM II. This multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping provides a 1.45μm tunable broadband Raman pump source by back-Raman amplification of the broadband seed light. Working together with the 1.5μm Brillouin pump, it can achieve ultra-wideband multi-wavelength random fiber laser output. By simultaneously tuning the output wavelengths of the Brillouin pump and the Raman pump, wavelength tuning of the broadband multi-wavelength random fiber laser can be achieved.

Description

Technical Field

[0001] This invention relates to the field of fiber laser technology, specifically to a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping. Background Technology

[0002] With the rapid development of fiber optic communication and sensing technologies, systems are placing higher demands on transmission capacity. Multi-wavelength fiber lasers eliminate the complex structures associated with combining multiple single-wavelength lasers, offering advantages such as compact structure, high efficiency, and low cost, providing new options for numerous fields including fiber optic sensing, spectral analysis, and fiber optic communication. Random fiber lasers rely on random scattering feedback, eliminating the need for a fixed resonant cavity. This unique structure gives them numerous advantages, including mode-free characteristics, simple structure, low noise, high efficiency, and good stability, making them an ideal carrier for realizing multi-wavelength random fiber laser output.

[0003] Existing multi-wavelength random fiber lasers mainly employ two methods: stimulated Brillouin scattering cascade or the introduction of wavelength-selective structures.

[0004] However, the output bandwidth of existing multi-wavelength Brillouin random fiber lasers still needs improvement. Furthermore, current multi-wavelength Brillouin and Raman random fiber lasers use fixed-wavelength Raman pumping, achieving wavelength tuning solely through tuning the Brillouin pump wavelength. This results in the inability to maintain broadband characteristics during wavelength tuning.

[0005] Therefore, there is an urgent need to develop a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping. Summary of the Invention

[0006] The purpose of this section is to outline some aspects of the embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0007] 1. Technical problems to be solved:

[0008] To address the issues mentioned above, such as the need to improve the output bandwidth of existing multi-wavelength Brillouin random fiber lasers and the inability to maintain broadband characteristics during wavelength tuning, this invention is proposed.

[0009] Therefore, the objective of this invention is to provide a tunable broadband Raman-pumped multi-wavelength Brillouin and Raman random fiber laser to achieve ultra-wideband multi-wavelength random fiber laser output. By simultaneously tuning the output wavelengths of the Brillouin pump and Raman pump, wavelength tuning of the broadband multi-wavelength random fiber laser can be achieved.

[0010] 2. Technical Solution:

[0011] To address the aforementioned technical problems, according to one aspect of the present invention, the present invention provides the following technical solution:

[0012] A multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping includes a 1.5μm Brillouin pump, a 1.45μm tunable broadband Raman pump, a wavelength division multiplexer, and a passive fiber.

[0013] in:

[0014] The 1.45μm tunable broadband Raman pump includes a wavelength-tunable cascaded random Raman fiber laser, a wavelength division multiplexer II, and a single-mode fiber I. The wavelength-tunable cascaded random Raman fiber laser is injected into the single-mode fiber I through the wavelength division multiplexer II.

[0015] The 1.45μm tunable broadband Raman pump also includes isolator two, a 1.45μm superluminescent diode, isolator one, and wavelength division multiplexer three. The 1.45μm superluminescent diode is injected into the single-mode fiber one through isolator one and wavelength division multiplexer three.

[0016] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping, wherein the wavelength-tunable cascaded random Raman fiber laser includes a 1μm band pump source, a fiber combiner, a single-mode fiber II, a wavelength-tunable point feedback unit, and an isolator III. The 1μm band pump source is injected into the single-mode fiber II through the pump end of the fiber combiner, and the signal end of the fiber combiner is connected to the wavelength-tunable point feedback unit.

[0017] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is provided, wherein the output spectral width of the 1.45μm tunable broadband Raman pump is ≥10nm and the output power is ≥1W.

[0018] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is wherein the tunable range of the output spectrum of the 1.45μm tunable broadband Raman pump is 1435nm to 1465nm.

[0019] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is provided, wherein the output power of the wavelength-tunable cascaded random Raman fiber laser is ≥2W and the output wavelength is tunable in the range of 1320-1370nm.

[0020] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is provided, wherein the multi-wavelength Brillouin and Raman random fiber laser generated by the wavelength tunable cascaded random Raman fiber laser has an output bandwidth ≥ 40 nm and an output spectrum tunable range of 1520-1580 nm.

[0021] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is wherein the passive fiber is a dispersion-compensating fiber.

[0022] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is wherein the passive fiber is a scattering-enhanced fiber.

[0023] As a preferred embodiment of the present invention, a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping is provided, wherein the passive fiber is composed of a dispersion-compensating fiber and a scattering-enhancing fiber connected in series.

[0024] 3. Beneficial effects:

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] This multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping uses a 1.45μm tunable broadband light source as the Raman pump for the multi-wavelength Brillouin and Raman random fiber laser, which can effectively increase its output bandwidth.

[0027] This multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping proposes to simultaneously tune the 1.45μm tunable broadband Raman pump wavelength and the 1.5μm Brillouin pump wavelength, which can maintain broadband characteristics while tuning the output wavelength of the multi-wavelength Brillouin and Raman random fiber laser. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0029] Figure 1 This is a schematic diagram of a 1.45μm tunable broadband Raman pump structure based on a tunable broadband Raman pumped multiwavelength Brillouin and Raman random fiber laser according to the present invention.

[0030] Figure 2 This is a schematic diagram of the structure of a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to the present invention.

[0031] Figure 3 This is a schematic diagram of a wavelength-tunable cascaded random Raman fiber laser structure based on a tunable broadband Raman-pumped multi-wavelength Brillouin and Raman random fiber laser according to the present invention.

[0032] Figure 4 This is the output spectrum of a broadband multi-wavelength Brillouin and Raman random fiber laser, as shown in Embodiment 1 of the present invention, which is based on a tunable broadband Raman-pumped multi-wavelength Brillouin and Raman random fiber laser.

[0033] The labels in the diagram are as follows: 1. 1.5μm Brillouin pump; 2. 1.45μm tunable broadband Raman pump; 3. Wavelength division multiplexer I; 4. Dispersion-compensating fiber; 201. Wavelength-tunable cascaded random Raman fiber laser; 202. Wavelength division multiplexer II; 203. Single-mode fiber I; 204. Wavelength division multiplexer III; 205. Isolator I; 206. 1.45μm superluminescent diode; 207. Isolator II; 2011. 1μm band pump source; 2012. Fiber combiner; 2013. Single-mode fiber II; 2014. Wavelength-tunable point feedback unit; 2015. Isolator III. Detailed Implementation

[0034] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] This invention is described in detail with reference to the schematic diagrams. When describing the embodiments of this invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not be construed as limiting the scope of protection of this invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0036] The orientation or positional relationship indicated in the terminology is based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing the invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention.

[0037] The term "connection method" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0038] The embodiments of the present invention will now be described in further detail with reference to the accompanying drawings.

[0039] This invention provides an overall structural schematic diagram of an embodiment of a tunable broadband Raman-pumped multiwavelength Brillouin and Raman random fiber laser, including:

[0040] Please see Figures 1-4 This embodiment of a multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping includes a 1.5μm Brillouin pump 1, a 1.45μm tunable broadband Raman pump 2, a wavelength division multiplexer 3, and a passive fiber.

[0041] in:

[0042] The 1.45μm tunable broadband Raman pump 2 includes a wavelength-tunable cascaded random Raman fiber laser 201, a wavelength division multiplexer 202, and a single-mode fiber 203. The wavelength-tunable cascaded random Raman fiber laser 201 is injected into the single-mode fiber 203 through the wavelength division multiplexer 202.

[0043] The 1.45μm tunable broadband Raman pump 2 also includes isolator 207, 1.45μm superluminescent diode 206, isolator 1 205, and wavelength division multiplexer 3 204. The 1.45μm superluminescent diode 206 is injected into single-mode fiber 1 203 via isolator 1 205 and wavelength division multiplexer 3 204. The wavelength-tunable cascaded random Raman fiber laser 201 back-amplifies the broadband seed light output from the 1.45μm superluminescent diode 206 in single-mode fiber 1 203 using stimulated Raman scattering effect. The amplified 1.45μm tunable broadband light is output through isolator 2 207.

[0044] It is worth noting that, specifically, the wavelength-tunable cascaded random Raman fiber laser 201 includes a 1μm band pump source 2011, an optical fiber combiner 2012, a single-mode fiber 2013, a wavelength-tunable point feedback unit 2014, and an isolator 3 2015. The 1μm band pump source 2011 is injected into the single-mode fiber 2013 through the pump end of the optical fiber combiner 2012. The signal end of the optical fiber combiner 2012 is connected to the wavelength-tunable point feedback unit 2014. Under the combined action of pumping, stimulated Raman scattering, backscattering Rayleigh scattering, and point feedback, the lased 1.35μm band cascaded random Raman fiber laser is output through the isolator 3 2015.

[0045] Next, specifically, the output spectral width of the 1.45μm tunable broadband Raman pump 2 is ≥10nm, preferably 11nm, and the output power is ≥1W, preferably 1.2W. The spectral width of ≥10nm is the key to achieving multi-wavelength output, and the power of ≥1W is the threshold for achieving sufficient gain.

[0046] Meanwhile, specifically, the tunable range of the output spectrum of the 1.45μm tunable broadband Raman pump 2 is 1435nm to 1465nm. At multiple wavelength points such as 1440nm, 1455nm and 1460nm, the system can achieve stable multi-wavelength laser output. As a preferred embodiment of the present invention, the output wavelength of the 1.45μm tunable broadband Raman pump 2 is set at 1455nm.

[0047] Furthermore, specifically, the output power of the wavelength-tunable cascaded random Raman fiber laser 201 is ≥2W, and the output wavelength is tunable in the range of 1320-1370nm. As a preferred embodiment of the present invention, the output wavelength of the wavelength-tunable cascaded random Raman fiber laser 201 is set at 1350nm.

[0048] It is worth noting that, specifically, the multi-wavelength Brillouin and Raman random fiber laser output bandwidth generated by the wavelength-tunable cascaded random Raman fiber laser 201 is ≥40nm, and the output spectrum is tunable in the range of 1520-1580nm. As a preferred embodiment of the present invention, the output spectrum is tunable in the range of 1550nm.

[0049] Specifically, the passive optical fiber is dispersion-compensating fiber 4.

[0050] Next, specifically, the passive optical fiber is a scattering-enhanced optical fiber.

[0051] Finally, specifically, passive optical fiber is composed of dispersion-compensating fiber and scattering-enhancing fiber connected in series.

[0052] Example 1

[0053] The structure of a tunable broadband Raman-pumped multiwavelength Brillouin and Raman random fiber laser is shown in the attached figure. Figure 2 As shown, a 1.45μm tunable broadband Raman pump 2 and a 1.5μm Brillouin pump 1 are injected into a dispersion-compensating fiber 4 via a wavelength division multiplexer 3. Under the influence of backscattering from the 1.45μm tunable broadband Raman pump 2, the 1.5μm Brillouin pump 1, and the dispersion-compensating fiber 4, a cascaded Brillouin random fiber laser is lased in the dispersion-compensating fiber 4. Since the output bandwidth of the 1.45μm tunable broadband Raman pump 2 is ≥10nm, broadband multi-wavelength Brillouin and Raman random fiber laser output can be effectively realized.

[0054] It is worth noting that the structure of the 1.45μm tunable broadband Raman pump 2 is shown in the attached figure. Figure 1 As shown, a 1.3μm wavelength-tunable cascaded random Raman fiber laser 201 is injected into a single-mode fiber 203 via wavelength division multiplexing (WDM) 202. A 1.45μm superluminescent diode 206 is injected into the single-mode fiber 203 via isolator 205 and WDM 3 204. The wavelength-tunable cascaded random Raman fiber laser 201 back-amplifies the broadband seed light output from the 1.45μm superluminescent diode 206 in the single-mode fiber 203 using stimulated Raman scattering. The amplified 1.45μm tunable broadband light exhibits high power and low noise. The generated 1.45μm tunable broadband light is further output through isolator 207. The residual pump light in the single-mode fiber 203 is output through the transmission end of WDM 3 204.

[0055] Next, the structure of the 1.3μm wavelength-tunable cascaded random Raman fiber laser 201 is shown in the attached figure. Figure 3 As shown, a 1μm band pump source 2011 is injected into a single-mode fiber 2013 through the pump end of an optical fiber combiner 2012. The signal end of the optical fiber combiner 2012 is connected to a wavelength-tunable point feedback unit 2014. Under the combined action of pumping, stimulated Raman scattering, backscattering Rayleigh scattering, and point feedback, first to fourth order random Raman fiber lasers are generated sequentially. The generated 1.35μm band fourth order random Raman fiber laser is output through isolator 2015.

[0056] Simultaneously, under the combined action of 1.45μm tunable broadband Raman pump 2 and 1.5μm Brillouin pump 1, broadband multi-wavelength Brillouin and Raman random fiber laser output can be generated, and its output spectrum is shown in the attached figure. Figure 4As shown. Furthermore, traditional multi-wavelength Brillouin and Raman random fiber lasers employ fixed-wavelength Raman pumping. When tuning the Brillouin pump output wavelength, the output bandwidth of the generated multi-wavelength Brillouin and Raman random fiber laser gradually narrows. In this invention, the wavelength of the 1.45μm broadband Raman pump is tunable. By simultaneously tuning the wavelengths of the Raman pump and the Brillouin pump, the multi-wavelength Brillouin and Raman random fiber laser can maintain its broadband output characteristics during wavelength tuning.

[0057] Therefore, this invention employs the aforementioned tunable broadband Raman-pumped multi-wavelength Brillouin and Raman random fiber laser to construct a 1.45μm tunable broadband light source as the Raman pump for the multi-wavelength Brillouin and Raman random fiber laser, effectively increasing its output bandwidth to over 50nm. Furthermore, simultaneously tuning the 1.45μm tunable broadband Raman pump wavelength and the 1.5μm Brillouin pump wavelength maintains broadband characteristics while tuning the output wavelength of the multi-wavelength Brillouin and Raman random fiber laser.

[0058] In addition, the circuits, electronic components and modules involved in this invention are all existing technologies, which can be fully implemented by those skilled in the art, and need not be elaborated upon. The content protected by this invention does not involve any improvement to the internal structure and method.

[0059] Although the present invention has been described above with reference to embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, as long as there is no structural conflict, the features in the disclosed embodiments can be combined with each other in any manner. The lack of an exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, the present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping, characterized in that, It includes a 1.5μm Brillouin pump (1), a 1.45μm tunable broadband Raman pump (2), a wavelength division multiplexer (3), and passive optical fiber; in: The 1.45μm tunable broadband Raman pump (2) includes a wavelength tunable cascaded random Raman fiber laser (201), a wavelength division multiplexer II (202), and a single-mode fiber I (203). The wavelength tunable cascaded random Raman fiber laser (201) is injected into the single-mode fiber I (203) through the wavelength division multiplexer II (202). The 1.45μm tunable broadband Raman pump (2) also includes isolator two (207), 1.45μm superluminescent diode (206), isolator one (205) and wavelength division multiplexer three (204), wherein the 1.45μm superluminescent diode (206) is injected into the single-mode fiber one (203) through isolator one (205) and wavelength division multiplexer three (204).

2. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 1, characterized in that, The wavelength-tunable cascaded random Raman fiber laser (201) includes a 1μm band pump source (2011), an optical fiber combiner (2012), a single-mode fiber II (2013), a wavelength-tunable point feedback unit (2014), and an isolator III (2015). The 1μm band pump source (2011) is injected into the single-mode fiber II (2013) through the pump end of the optical fiber combiner (2012), and the signal end of the optical fiber combiner (2012) is connected to the wavelength-tunable point feedback unit (2014).

3. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 2, characterized in that, The output spectral width of the 1.45μm tunable broadband Raman pump (2) is ≥10nm, and the output power is ≥1W.

4. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 3, characterized in that, The output spectrum of the 1.45μm tunable broadband Raman pump (2) is tunable from 1435nm to 1465nm.

5. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 4, characterized in that, The output power of the wavelength-tunable cascaded random Raman fiber laser (201) is ≥2W, and the output wavelength is tunable in the range of 1320-1370nm.

6. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 5, characterized in that, The wavelength-tunable cascaded random Raman fiber laser (201) generates a multi-wavelength Brillouin and Raman random fiber laser with an output bandwidth ≥40nm and an output spectrum tunable range of 1520-1580nm.

7. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 1, characterized in that, The passive optical fiber is a dispersion-compensating optical fiber (4).

8. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 1, characterized in that, The passive optical fiber is a scattering-enhanced optical fiber.

9. The multi-wavelength Brillouin and Raman random fiber laser based on tunable broadband Raman pumping according to claim 1, characterized in that, The passive optical fiber is composed of dispersion-compensating fiber and scattering-enhancing fiber connected in series.

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