CN117559213B - Stimulated Brillouin effect control device and application thereof - Google Patents

Abstract

The invention belongs to the technical field of lasers, and particularly relates to an stimulated Brillouin effect control device and application thereof, wherein the stimulated Brillouin effect control device comprises a deformation column, the deformation column is composed of an elastic connector, n bow-shaped deformation units A and n bow-shaped deformation units B, and n is more than or equal to 2; the arch-shaped deformation units A and B comprise arch-shaped sheets, and two ends of each arch-shaped sheet are respectively connected with two ends of each piezoelectric ceramic column to form a string-matching arch; the gain optical fiber is wound on the deformation column along the spiral track; the 2 piezoelectric ceramic columns of the same deformation unit are driven by 1 piezoelectric ceramic driver, and n piezoelectric ceramic drivers are connected with the controller. The stress on the gain fiber is accurate and controllable, the applied voltage frequency can be adjusted, and when the gain fiber is used for a high-power single-frequency narrow-linewidth fiber laser, the SBS effect can be eliminated; when the SBS optical fiber is applied to an SBS optical fiber laser, the SBS effect can be promoted.

Description

A stimulated Brillouin effect control device and its use

Technical field

The invention belongs to the field of laser technology, and specifically relates to a stimulated Brillouin effect control device and a high-power single-frequency narrow-linewidth fiber laser and an SBS fiber laser prepared using the device.

Background technique

The stimulated Brillouin (SBS) effect has the characteristics of low threshold, extremely narrow linewidth, and high coherence. Brillouin lasers based on this effect can be widely used in fiber sensing, fiber optic gyroscopes, coherent optical communications, and radio frequencies. Optical fiber transmission and other fields.

In Brillouin lasers, the SBS effect is a beneficial effect, and promoting the SBS effect is conducive to achieving efficient Stokes light generation.

As a high-performance light source, high-power single-frequency narrow linewidth light source has important applications in the fields of coherent beam combining, quantum information, lidar, coherent measurement and other fields. The mainstream solution for this type of light source is the main oscillator power amplification (MOPA) fiber laser. . In this type of laser, the SBS effect is a harmful effect, which limits the increase in laser power. The SBS effect introduces additional noise and the Stokes light generated during the SBS process can easily cause damage to devices in the optical path. Therefore, in this type of laser, the SBS effect needs to be strictly limited to prevent the occurrence of the SBS process.

Currently, there are four main methods to suppress SBS: increasing the mode field area, reducing the gain coefficient, broadening the gain spectrum, and reducing the gain length. However, the above methods all have insurmountable pain points. The method of increasing the mode field area is to reduce the pump light power density by increasing the fiber core size to suppress SBS. However, due to the increase in the fiber core size, high-order transverse modes are easily generated and the beam quality is poor, resulting in this type of The method cannot be applied to fiber lasers that have high requirements for beam quality; the method of reducing the gain coefficient is to reduce the overlap of the optical wave field and the acoustic wave field in the fiber core by changing the doping components in the fiber core to achieve the purpose of suppressing SBS, but The manufacturing process of this type of optical fiber is extremely complex, and there are inevitable problems such as lowering the fiber damage threshold and serious photon darkening, which makes this method unable to be widely used; the broadened gain spectrum method changes the SBS center frequency shift by changing the sound speed in the optical fiber. The purpose of making Stokes light of a single frequency unable to accumulate gain to broaden the gain spectrum and suppress the SBS effect is usually divided into methods of applying temperature/stress outside the fiber or by using fiber doped with special components that can cause stress changes in the fiber, which will cause temperature or stress It is difficult to apply a large gradient range on the fiber and may damage the fiber. Therefore, the effect of suppressing SBS is very limited and can usually only be used as an auxiliary method. The reduction of gain length method reduces the SBS gain by shortening the length of the gain fiber, which is the purpose of the SBS effect. , but this is based on the sacrifice of laser efficiency, so it has limitations.

In the prior art, promoting the SBS effect and inhibiting the SBS effect are achieved through different devices respectively. There is almost no device that can both promote the SBS effect and inhibit the SBS effect.

Contents of the invention

The technical problem to be solved by the present invention is to make up for the shortcomings of the existing technology and provide a stimulated Brillouin effect control device and a high-power single-frequency narrow linewidth fiber laser and an SBS fiber laser prepared by applying the device.

To solve the above technical problems, the technical solution of the present invention is:

A stimulated Brillouin effect control device includes a deformation column. The deformation column is composed of an elastic connector, n arcuate deformation units A and n arcuate deformation units B, n≥2;

Both the arcuate deformation unit A and the arcuate deformation unit B include an arched piece, the two ends of the arched piece are respectively connected to the two ends of the piezoelectric ceramic column, forming a matching bow shape;

The arcuate deformation unit A is processed with a first spiral groove, and the arcuate deformation unit B is processed with a second spiral groove;

One arcuate deformation unit A and one arcuate deformation unit B are fixed face-to-face on both sides of the elastic connector to form a complete deformation unit; n deformation units are stacked to form deformation columns, and n first spiral grooves and n second spiral grooves are located in the same spiral trajectory; the gain fiber is wound along the spiral trajectory in n first spiral grooves and n second spiral grooves;

Two piezoelectric ceramic columns of the same deformation unit are driven by one piezoelectric ceramic actuator, and n piezoelectric ceramic actuators are connected to the controller.

Further, each deformation unit is matched with one chip temperature sensor, and the chip temperature sensor is attached to the gain optical fiber segment on the corresponding deformation unit; n chip temperature sensors are all connected to the controller.

Further, both the arcuate deformation unit A and the arcuate deformation unit B are composed of a first straight piece, an arched piece, a second straight piece and a piezoelectric ceramic column connected end to end, forming a coordinated bow shape.

Further, the first straight piece, the arched piece and the second straight piece of the arcuate deformation unit A are integrally formed of copper or aluminum; the first straight piece, the arched piece and the second straight piece of the arcuate deformation unit B are Made of copper or aluminum in one piece.

Furthermore, the material of the elastic connecting body is high resilience sponge.

A high-power single-frequency narrow-linewidth fiber laser, including a stimulated Brillouin effect control device as described above, a single-frequency narrow-linewidth seed source, a first signal optical isolator, a mode field adapter and a pump light stripper The integrated component, the gain fiber of the stimulated Brillouin effect control device, and the main interface of the pump optical beam combiner are connected in series through the energy transmission optical fiber; the first branch interface of the pump optical beam combiner and the second signal optical isolator are connected through the transmission optical fiber. The energy-transmitting optical fiber is connected in series, and the second branch port of the pump optical beam combiner and the pump source are connected in series through the energy-transmitting optical fiber.

Further, the first signal optical isolator is a low-power signal optical isolator, and the second signal optical isolator is a high-power signal optical isolator.

Further, the changing frequency of the voltage applied by the piezoelectric ceramic driver to the piezoelectric ceramic column is hundreds of kHz and above.

An SBS fiber laser, including the above-mentioned stimulated Brillouin effect control device, and a three-port circulator. The three ports of the three-port circulator are A, B, and C ports. The A port is connected to the pump light source. , the B port, the gain fiber of the stimulated Brillouin effect control device, the pump light adjustable attenuator, the pump light isolator and the optical wavelength division multiplexer are connected in turn through the energy transfer fiber, and the C port is connected to the optical wavelength division multiplexer Connected through energy-transmitting optical fibers.

Further, the SBS frequency shift on the corresponding gain fiber segment caused by the voltage applied by the piezoelectric ceramic driver to the piezoelectric ceramic column is: , the SBS frequency shift on the corresponding gain fiber segment caused by real-time temperature changes is/> , is a constant value.

The beneficial effects that can be achieved by this invention are:

(1) By applying a corresponding voltage to the piezoelectric ceramic column through the piezoelectric ceramic driver, the stress on the gain fiber can be accurately controlled and the frequency of the applied voltage can be adjusted.

(2) When the stimulated Brillouin effect control device is applied to a high-power single-frequency narrow linewidth fiber laser, the changing frequency of the voltage applied by the piezoelectric ceramic driver to the piezoelectric ceramic column is set to hundreds of kHz and above, resulting in The SBS center frequency shift in the gain fiber changes at a frequency of hundreds of kHz and above. This rapid change prevents the gain fiber from forming effective gain accumulation and the SBS process cannot be effectively established, thus fundamentally eliminating the SBS effect.

(3) When the stimulated Brillouin effect control device is applied to an SBS fiber laser, the controller applies a corresponding voltage to the piezoelectric ceramic column through the piezoelectric ceramic driver based on the real-time temperature feedback from the chip temperature sensor to achieve gain. The stress on the optical fiber is accurately controllable, so it responds quickly to compensate for the change in sound speed in the gain fiber caused by temperature changes, achieving the same effect of the sound speed in the entire gain fiber, so that the center frequency of the SBS in the gain fiber is a constant value, improving SBS gain promotes the SBS effect.

(4) The stimulated Brillouin effect control device can not only inhibit the SBS effect, but also promote the SBS effect, and the degree of inhibition and promotion is controllable.

Description of the drawings

Figure 1 is a perspective view of Embodiment 1 of the present invention.

Figure 2 is a front view of Embodiment 1 of the present invention.

Figure 3 is a perspective view of the deformable column in Embodiment 1 of the present invention.

Figure 4 is a front view of the deformable column in Embodiment 1 of the present invention.

Figure 5 is a side view of the deformable column in Embodiment 1 of the present invention.

Figure 6 is a structural diagram of Embodiment 2 of the present invention.

Figure 7 is a structural diagram of Embodiment 3 of the present invention.

In the picture: 1-single frequency narrow linewidth seed source, 2-first signal optical isolator, 3-mode field adapter and pump optical stripper integrated assembly, 4-stimulated Brillouin effect control device, 5-pump Pump light combiner, 6-second signal optical isolator, 7-pump source, 8-three-port circulator, 9-pump light adjustable attenuator, 10-pump light isolator, 11-optical wavelength division multiplexer utensil; utensil;

41-Deformation column, 42-Gain optical fiber, 43-SMD temperature sensor,

411 - Bow deformation unit A, 412 - Bow deformation unit B, 413 - Elastic connector,

4111-The first straight piece, 4112-Arched piece, 4113-Piezoelectric ceramic column, 4114-The second straight piece, 4115-The first spiral groove, 4125-The second spiral groove.

Detailed ways

The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Example 1

A stimulated Brillouin effect control device 4 includes a deformation column 41, a gain fiber 42, a patch temperature sensor 43 and a controller.

The deformation column 41 is composed of an elastic connector 413, 15 arcuate deformation units A411 and 15 arcuate deformation units B412. The material of the elastic connector 413 is high resilience sponge.

The arcuate deformation unit A411 and the arcuate deformation unit B412 are composed of a first straight piece 4111, an arched piece 4112, a second straight piece 4114 and a piezoelectric ceramic column 4113 connected end to end, forming a coordinated bow shape; the arcuate deformation unit A411 The first straight piece 4111, the arched piece 4112 and the second straight piece 4114 are integrally formed of copper material (can also be made of aluminum or composite materials); the first straight piece 4111, the arched piece 4112 and the arcuate deformation unit B412 The second straight piece 4114 is integrally formed of copper material; the piezoelectric ceramic pillar 4113 in this embodiment is a 5VS6 PZT from Harbin Core Tomorrow Technology Co., Ltd.;

The arcuate deformation unit A411 is processed with a first spiral groove 4115, and the arcuate deformation unit B412 is processed with a second spiral groove 4125; one arcuate deformation unit A411 and one arcuate deformation unit B412 are fixed face to face on both sides of the elastic connector 413 , forming a complete deformation unit; 15 deformation units are stacked (there is no connection relationship between two adjacent deformation units), forming a deformation column 41, 15 first spiral grooves 4115 and 15 second spiral grooves 4125 is in the same spiral trajectory.

The gain optical fiber 42 is wound along the spiral trajectory in 15 first spiral grooves 4115 and 15 second spiral grooves 4125. Each deformation unit is matched with a chip temperature sensor 43, and the chip temperature sensor 43 is attached to the corresponding deformation unit. On the gain fiber section on The gain fiber 42 is a 10m long erbium-doped single-mode gain fiber;

The two piezoelectric ceramic columns 4113 of the same deformation unit are driven by one piezoelectric ceramic driver, and the 15 piezoelectric ceramic drivers and 15 chip temperature sensors 43 are all connected to the controller.

In fiber lasers, the backward Brillouin frequency shift is: , of which/> is the pump light wavelength/> The effective refractive index at ,/> is the speed of sound in the optical fiber. When the gain fiber and pump light are selected, only the sound speed in the fiber is a variable, so the SBS frequency shift can be controlled by controlling the sound speed.

The SBS gain spectrum can be expressed as ,/> is the change amount of SBS center frequency shift,/> is the attenuation coefficient of acoustic phonons.

If the SBS center frequency shift in the gain fiber changes at a frequency of hundreds of kHz and above, this rapid change prevents the gain fiber from forming effective gain accumulation, and the SBS process cannot be effectively established, thus fundamentally eliminating the SBS effect. Based on this theory, Embodiment 2 was designed.

If the SBS process in the gain fiber has no influence (such as maintaining/> Consistent or complete elimination/> ), then the energy of the pump light will be concentrated and transferred to a central frequency Stokes photon, thereby achieving high gain and promoting the SBS effect. Based on this theory, Embodiment 3 was designed.

Example 2

A high-power single-frequency narrow-linewidth fiber laser includes the stimulated Brillouin effect control device 4 of Embodiment 1, a single-frequency narrow-linewidth seed source 1, and a first signal optical isolator 2 (low-power signal optical isolator ), the mode field adapter and the pump light stripper integrated component 3, the gain fiber 42 of the stimulated Brillouin effect control device, and the main interface of the pump light combiner 5 are connected in series through the energy transfer fiber; the pump light combiner The first branch interface of 5 and the second signal optical isolator 6 (high-power signal optical isolator) are connected in series through the energy-transmitting optical fiber. The second branch interface of the pump optical beam combiner 5 and the pump source are connected in series through the energy-transmitting optical fiber. .

The SBS effect in high-power single-frequency narrow-linewidth fiber lasers is a harmful effect and needs to be suppressed or eliminated. In this embodiment, the signal light (wavelength 1550nm) emitted from the single-frequency narrow linewidth seed source 1 enters the stimulated Brillouin effect after passing through the first signal optical isolator 2, the mode field adapter and the pump light stripper integrated component 3 Control device 4, at the same time, the pump light (976nm) emitted from the pump source 7 is coupled into the stimulated Brillouin effect control device 4 through the pump light combiner 5, and the signal light is simultaneously generated in the stimulated Brillouin effect control device 4 The amplification and SBS effect elimination process realizes the improvement of the upper limit of signal light amplification power, thereby realizing high-power signal light. The amplified signal light is output after passing through the pump light combiner 5 and the second signal light isolator 6 , thereby realizing high-power single-frequency narrow linewidth laser.

The changing frequency of the voltage applied by the piezoelectric ceramic driver to the piezoelectric ceramic column 4113 is hundreds of kHz and above (for example, reaching the MHz level), which causes the SBS center frequency shift in the gain fiber to change at a frequency of hundreds of kHz and above. This Rapid changes prevent the gain fiber from forming effective gain accumulation and the SBS process cannot be effectively established, thus fundamentally eliminating the SBS effect.

Example 3

An SBS fiber laser, characterized by: including the stimulated Brillouin effect control device 4 of Embodiment 1, and a three-port circulator 8. The three ports of the three-port circulator 8 are A, B, and C ports respectively. The A port is connected to the pump light source, and the B port, the gain fiber 42 of the stimulated Brillouin effect control device, the pump light adjustable attenuator 9, the pump optical isolator 10 and the optical wavelength division multiplexer 11 pass through the transmission line in sequence. The C port is connected to the optical wavelength division multiplexer 11 through a power transmission optical fiber.

The 1550nm pump light is incident through the A port of the three-port circulator 8, exits through the B port, and is coupled into the gain fiber 42 in the stimulated Brillouin effect control device 4, and passes through the action of the stimulated Brillouin effect control device 4. The enhancement of the SBS effect is achieved, thereby efficiently generating 1550.087nm reverse Stokes light transmitted from right to left. It is incident through the B port of the three-port circulator 8 and then output by the C port and passes through the optical wavelength division multiplexer 11 to achieve the final result. Stokes light output. The unconsumed 1550nm pump light passes through the pump light adjustable attenuator 9 and the pump light isolator 10 to realize power adjustment, and is finally coupled and output through the optical wavelength division multiplexer 11. When the pump light adjustable attenuator 9 attenuates the pump light intensity to 0, the system is a standard single-wavelength SBS laser; when the pump light adjustable attenuator 9 does not attenuate the pump light intensity to 0, the system The system is a dual-wavelength SBS laser.

The SBS frequency shift on the corresponding gain fiber segment caused by the voltage applied by the piezoelectric ceramic driver to the piezoelectric ceramic column 4113 is , the SBS frequency shift on the corresponding gain fiber segment caused by real-time temperature changes is/> ,/> is a constant value, that is:/> . Then the SBS center frequency in the entire gain fiber is a constant value, ensuring that the energy of the pump light will be concentrated into Stokes photons at a central frequency, thereby achieving high gain and promoting the SBS effect.

Claims (10)

1. The stimulated Brillouin effect control device is characterized in that: comprises a deformation column (41), wherein the deformation column (41) is composed of an elastic connector (413), n arc deformation units A (411) and n arc deformation units B (412), and n is more than or equal to 2;

the arc deformation unit A (411) and the arc deformation unit B (412) comprise arc-shaped sheets (4112), and two ends of each arc-shaped sheet (4112) are respectively connected with two ends of each piezoelectric ceramic column (4113) to form a string-matching arc shape;

a first spiral groove (4115) is formed in the arc-shaped deformation unit A (411), and a second spiral groove (4125) is formed in the arc-shaped deformation unit B (412);

the 1 arch-shaped deformation unit A (411) and the 1 arch-shaped deformation unit B (412) are fixed on two sides of the elastic connecting body (413) face to form 1 complete deformation unit; n deformation units are laminated to form a deformation column (41), and n first spiral grooves (4115) and n second spiral grooves (4125) are positioned in the same spiral track; -the gain fiber (42) is wound in n first spiral grooves (4115) and n second spiral grooves (4125) along the spiral trajectory;

the 2 piezoelectric ceramic columns (4113) of the same deformation unit are driven by 1 piezoelectric ceramic driver, and n piezoelectric ceramic drivers are connected with a controller.

2. The stimulated brillouin effect control apparatus of claim 1, wherein: each deformation unit is matched with 1 patch temperature sensor (43), and the patch temperature sensors (43) are attached to gain optical fiber segments on the corresponding deformation units; and n patch temperature sensors (43) are connected with the controller.

3. The stimulated brillouin effect control apparatus of claim 1, wherein: the arc deformation unit A (411) and the arc deformation unit B (412) are formed by connecting a first straight sheet (4111), an arc sheet (4112), a second straight sheet (4114) and a piezoelectric ceramic column (4113) end to end and form a chord-matched arc shape.

4. The stimulated brillouin effect control apparatus of claim 3, wherein: the first straight sheet (4111), the arched sheet (4112) and the second straight sheet (4114) of the arched deformation unit A (411) are integrally formed by copper or aluminum; the first straight piece (4111), the arched piece (4112) and the second straight piece (4114) of the arched deformation unit B (412) are integrally formed by copper or aluminum.

5. The stimulated brillouin effect control apparatus of claim 1, wherein: the elastic connector (413) is made of high-resilience sponge.

6. A high-power single-frequency narrow linewidth fiber laser is characterized in that: the stimulated Brillouin effect control device comprises the stimulated Brillouin effect control device according to claim 1, wherein a single-frequency narrow-linewidth seed source (1), a first signal optical isolator (2), a mode field adapter and pump light stripper integrated piece (3), a gain optical fiber (42) of the stimulated Brillouin effect control device and a main interface of a pump light combiner (5) are sequentially connected in series through energy transmission optical fibers; the first sub-interface of the pumping beam combiner (5) is connected with the second signal optical isolator (6) in series through an energy transmission optical fiber, and the second sub-interface of the pumping beam combiner (5) is connected with the pumping source in series through an energy transmission optical fiber.

7. The high power single frequency narrow linewidth fiber laser of claim 6 wherein: the first signal optical isolator (2) is a low-power signal optical isolator, and the second signal optical isolator (6) is a high-power signal optical isolator.

8. The high power single frequency narrow linewidth fiber laser of claim 6 wherein: the frequency of change of the voltage applied to the piezoelectric ceramic column (4113) by the piezoelectric ceramic driver is hundred kHz and above.

9. An SBS fiber laser, characterized by: the stimulated brillouin effect control device comprises the stimulated brillouin effect control device according to claim 1 or 2, and further comprises a three-port circulator (8), wherein three ports of the three-port circulator (8) are A, B, C ports respectively, an A port is connected with a pump light source, a B port, a gain fiber (42) of the stimulated brillouin effect control device, a pump light adjustable attenuator (9), a pump light isolator (10) and an optical wavelength division multiplexer (11) are sequentially connected through an energy transmission fiber, and a C port is connected with the optical wavelength division multiplexer (11) through the energy transmission fiber.

10. The SBS fiber laser of claim 9, wherein: SBS frequency shift on the corresponding gain fiber section caused by the voltage applied by the piezoelectric ceramic driver to the piezoelectric ceramic column (4113) is as followsSBS frequency shift on the corresponding gain fiber section caused by real-time temperature change is +.>，/>Is a constant value.