Low noise semiconductor laser

Abstract

The utility model discloses a kind of low-noise semiconductor lasers, it is related to the technical field of semiconductor laser.Low-noise semiconductor laser includes substrate, semiconductor gain medium, external resonant cavity and driving assembly, wherein, semiconductor gain medium is arranged in substrate, for generating optical signal;External resonant cavity is movably arranged in substrate, the entrance of external resonant cavity is opposite to the emission surface of semiconductor gain medium;Driving assembly is arranged in substrate and is driven to connect external resonant cavity, so that external resonant cavity is moved relative to substrate to approach or away from emission surface.The technical scheme provided by the utility model improves the stability of low-noise semiconductor laser.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor laser technology, and in particular to a low-noise semiconductor laser. Background Technology

[0002] Semiconductor lasers have been widely used in many fields due to their advantages such as small size, high efficiency, and long lifespan. In particular, low-noise semiconductor lasers play an important role in many fields such as communications, optical storage, sensing, and medicine.

[0003] Most existing low-noise semiconductor lasers reduce noise through material optimization and temperature control. However, during long-term operation or under different environmental conditions, the internal structure of low-noise semiconductor lasers is susceptible to changes due to vibration or shock, affecting their operational stability. Utility Model Content

[0004] The main objective of this invention is to propose a low-noise semiconductor laser, which aims to reduce noise while improving the stability of the low-noise semiconductor laser.

[0005] To achieve the above objectives, the present invention proposes a low-noise semiconductor laser, comprising:

[0006] substrate;

[0007] A semiconductor gain medium is disposed on the substrate, and the semiconductor gain medium is used to generate optical signals;

[0008] An external resonant cavity is movably disposed on the substrate, the entrance of the external resonant cavity being opposite to the emitting surface of the semiconductor gain medium; and,

[0009] A driving component is disposed on the substrate and driven to connect to the external resonant cavity, such that the external resonant cavity moves relative to the substrate to move closer to or further away from the emitting surface.

[0010] In one embodiment, the driving component includes:

[0011] A piezoelectric element is connected at one end to the external resonant cavity and at the other end to the substrate. The deformation of the piezoelectric element drives the external resonant cavity to move closer to or away from the emitting surface.

[0012] In one embodiment, the driving component further includes:

[0013] A sliding ball bearing is movably positioned on the side of the external resonant cavity facing the substrate; and,

[0014] A guide groove is provided on the substrate, and the sliding ball is tactilely connected to the guide groove.

[0015] In one embodiment, the low-noise semiconductor laser further includes:

[0016] A displacement detection element is disposed on the substrate, the displacement detection element being used to detect the movement stroke of the external resonant cavity; and,

[0017] The controller is electrically connected to the drive assembly and the displacement detection element.

[0018] In one embodiment, the external resonant cavity is configured as a ring cavity.

[0019] In one embodiment, the external resonant cavity includes:

[0020] A first substrate is movably disposed on the substrate, and the driving component is drivingly connected to the first substrate;

[0021] An isolation layer covering the first substrate; and,

[0022] A ring waveguide is disposed on the side of the isolation layer away from the first substrate, and the entrance is provided on the side of the ring waveguide near the emitting surface.

[0023] In one embodiment, the external resonant cavity further includes:

[0024] A coupling waveguide is provided at the entrance and has a gap between it and the ring waveguide. The coupling waveguide is used to guide the transmission of the optical signal between the semiconductor gain medium and the ring waveguide.

[0025] In one embodiment, the semiconductor gain medium includes a second substrate, a lower confinement layer, an active region, an upper confinement layer, a contact layer, and an electrode layer stacked sequentially. The second substrate is disposed on the substrate, and the active region has an emission surface at one end near the external resonant cavity.

[0026] In one embodiment, the semiconductor gain medium further includes:

[0027] A buffer layer is disposed between the second substrate and the lower limiting layer.

[0028] In one embodiment, the active region is configured as a quantum well structure.

[0029] This invention provides a low-noise semiconductor laser by incorporating a substrate, a semiconductor gain medium, an external resonant cavity, and a driving component. The semiconductor gain medium, located on the substrate, generates the optical signal. The external resonant cavity is movably mounted on the substrate, with its inlet facing the emitting surface of the semiconductor gain medium. The driving component, located on the substrate and connected to the external resonant cavity, allows the external resonant cavity to move relative to the substrate, moving closer to or further away from the emitting surface. Compared to existing low-noise semiconductor lasers that employ material optimization and temperature control, this invention, through its movable external resonant cavity, allows adjustment of the distance between the cavity's inlet and the emitting surface. This enables optimization of the optical signal transmission path under different operating conditions, compensating for external interference and ensuring stable optical signal output. Ultimately, this reduces noise while improving the stability of the low-noise semiconductor laser. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0031] Figure 1 A schematic diagram of a structure of an embodiment of the low-noise semiconductor laser provided by this utility model;

[0032] Figure 2 for Figure 1 A cross-sectional view of one embodiment.

[0033] Explanation of icon numbers:

[0034] 100. Substrate; 110. Side plate;

[0035] 200, Semiconductor gain dielectric; 210, Second substrate; 220, Buffer layer; 230, Lower confinement layer; 240, Active region; 241, Emitter surface; 250, Upper confinement layer; 260, Contact layer; 270, Electrode layer;

[0036] 300 External resonant cavity; 310 First substrate; 320 Isolation layer; 330 Ring waveguide; 340 Coupled waveguide;

[0037] 410. Piezoelectric element; 420. Sliding ball bearing; 430. Guide groove.

[0038] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0039] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0040] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0041] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0042] Semiconductor lasers have been widely used in many fields due to their advantages such as small size, high efficiency, and long lifespan. In particular, low-noise semiconductor lasers play an important role in many fields such as communications, optical storage, sensing, and medicine.

[0043] Most existing low-noise semiconductor lasers reduce noise through material optimization and temperature control. However, during long-term operation or under different environmental conditions, the internal structure of low-noise semiconductor lasers is susceptible to changes due to vibration or shock, affecting their operational stability.

[0044] This invention proposes a low-noise semiconductor laser to improve its stability while reducing noise.

[0045] Please see 1 and Figure 2 In one embodiment, the low-noise semiconductor laser includes a substrate 100, a semiconductor gain medium 200, an external resonant cavity 300, and a driving assembly.

[0046] The substrate 100 provides the basic support and mounting base for the entire low-noise semiconductor laser. In one embodiment, the substrate 100 includes a base plate and a side plate 110. The base plate has a mounting groove for providing a mounting base. Further, in one embodiment, the base plate also has a heat dissipation channel on the side opposite to the mounting groove to dissipate heat from the low-noise semiconductor laser. The heat dissipation channel can be an air-cooled channel or a liquid-cooled channel, and can be configured as an S-shaped, L-shaped, or U-shaped structure, etc., without limitation. Of course, in other embodiments, heat sinks can also be provided on the substrate 100, without limitation. Of course, in other embodiments, the base plate can also provide a mounting base by providing connection holes, etc., without limitation. In one embodiment, the substrate 100 is made of a ceramic material with high thermal conductivity to avoid heat concentration. Of course, in other embodiments, the substrate 100 can also be made of materials with good thermal conductivity, such as copper, aluminum, or silicon carbide, without limitation.

[0047] A semiconductor gain medium 200 is disposed on a substrate 100 for generating optical signals. In one embodiment, the semiconductor gain medium 200 is fixed to a mounting groove of the substrate 100, and an emitting surface 241 is provided on one side of the semiconductor gain medium 200. The optical signal generated by the semiconductor gain medium 200 is emitted from the emitting surface 241.

[0048] An external resonant cavity 300 is movably disposed on the substrate 100, with its inlet facing the emitting surface 241 of the semiconductor gain medium 200. In one embodiment, the external resonant cavity 300 is located on one side of the semiconductor gain medium 200, and its inlet faces the emitting surface 241 to ensure that the optical signal emitted through the emitting surface 241 can enter the external resonant cavity 300. In another embodiment, a gap exists between the inlet and the emitting surface 241 to facilitate the coupling of the optical signal into the external resonant cavity 300. In yet another embodiment, the outlet of the external resonant cavity 300 is positioned opposite the inlet, and the outlet is used to connect to external optical components. Thus, the external resonant cavity 300 provides a feedback path for the optical signal, allowing it to be reflected and circulated multiple times within the external resonant cavity 300, thereby enhancing the intensity and stability of the optical signal and reducing fluctuations and noise.

[0049] A driving component is disposed on the substrate 100 and drives the external resonant cavity 300, causing the external resonant cavity 300 to move relative to the substrate 100 to approach or move away from the emitting surface 241. In one embodiment, the driving component is located on the side of the external resonant cavity 300 away from the semiconductor gain medium 200 to avoid affecting the semiconductor gain medium 200. Thus, by setting the driving component to adjust the distance between the inlet and the emitting surface 241, it can be ensured that the mode of the optical signal always matches the mode of the external resonant cavity 300, reducing mode competition noise and improving the quality and stability of the optical signal.

[0050] The technical solution of this utility model involves assembling a substrate 100, a semiconductor gain medium 200, an external resonant cavity 300, and a driving component within a low-noise semiconductor laser. The semiconductor gain medium 200 is disposed on the substrate 100 and is used to generate optical signals. The external resonant cavity 300 is movably disposed on the substrate 100, with its inlet facing the emitting surface 241 of the semiconductor gain medium 200. The driving component is disposed on the substrate 100 and drives the external resonant cavity 300, allowing the external resonant cavity 300 to move relative to the substrate 100 to approach or move away from the emitting surface 241. Compared to existing low-noise semiconductor lasers that employ material optimization and temperature control, the technical solution of this utility model, by providing a movable external resonant cavity 300, allows adjustment of the distance between the inlet of the external resonant cavity 300 and the emitting surface 241. This enables optimization of the optical signal transmission path under different operating conditions to compensate for external interference, ensuring stable optical signal output, thereby reducing noise and improving the stability of the low-noise semiconductor laser.

[0051] Please see Figure 1 In one embodiment, the driving component includes a piezoelectric sheet 410, one end of which is connected to an external resonant cavity 300 and the other end of which is connected to a substrate 100. The deformation of the piezoelectric sheet 410 drives the external resonant cavity 300 to move closer to or further away from the emitting surface 241.

[0052] The piezoelectric element 410 exhibits the piezoelectric effect, meaning that under the influence of an electric field, it undergoes mechanical deformation, thereby driving the external resonant cavity 300 to move. In one embodiment, one end of the piezoelectric element 410 is connected to the external resonant cavity 300, and the other end is connected to the side plate 110. Electrodes are provided on both sides of the piezoelectric element 410, and the electrodes are connected to a driving circuit. The driving circuit can apply a positive or negative voltage to the electrodes, causing the piezoelectric element 410 to deform. The piezoelectric element 410 is made of piezoelectric ceramic materials with a piezoelectric effect, such as lead vanadate ceramic, lead zirconate titanate, or strontium niobate-doped lead titanate. The material of the piezoelectric element 410 is not limited here. In one embodiment, two piezoelectric elements 410 are spaced apart, located at opposite ends of the same side of the external resonator to ensure uniform driving of the external resonant cavity 300. Of course, in other embodiments, one or more piezoelectric elements 410 may be provided; the number of piezoelectric elements 410 is not limited here. Of course, in other embodiments, the drive component may also include a micro motor or a micro cylinder, etc., without limitation.

[0053] When a positive voltage is applied to the electrode by the driving circuit, the piezoelectric element 410 undergoes an extension deformation to move the external resonant cavity 300 closer to the emitting surface 241, reducing the distance between the inlet and the emitting surface 241. When a negative voltage is applied to the electrode by the driving circuit, the piezoelectric element 410 undergoes a compression deformation to increase the distance between the inlet and the emitting surface 241. When no voltage is applied to the electrode by the driving circuit, the piezoelectric element 410 remains stationary, thus positioning the external resonant cavity 300. In this way, the driving assembly allows the distance between the inlet and the emitting surface 241 to be dynamically adjusted to adapt to different conditions, improving the stability and flexibility of the low-noise semiconductor laser.

[0054] Please see Figure 1 and Figure 2 Furthermore, in one embodiment, the driving assembly further includes a sliding ball 420 and a guide groove 430. The sliding ball 420 is movably disposed on the side of the external resonant cavity 300 facing the substrate 100; the guide groove 430 is disposed on the substrate 100, and the sliding ball 420 is in rolling connection with the guide groove 430.

[0055] In one embodiment, the external resonant cavity 300 has a positioning groove on the side facing the substrate 100, and a sliding ball 420 is movably disposed in the positioning groove. Specifically, in one embodiment, multiple sliding balls 420 are spaced apart, and the positioning groove corresponds one-to-one with the sliding ball 420. In one embodiment, a guide groove 430 is provided and located at the center of the substrate 100, and a row of sliding balls 420 is provided correspondingly. Of course, in other embodiments, multiple guide grooves 430 may be provided, and sliding balls 420 may be provided correspondingly; this is not limited here. Of course, in other embodiments, the external resonant cavity 300 may also be provided with a slider, which is movably embedded in the guide groove 430; or, the contact surfaces between the external resonant cavity 300 and the substrate 100 may be smoothed; this is not limited here.

[0056] The technical solution of this embodiment of the utility model uses a piezoelectric element 410 to drive the movement of the external resonant cavity 300. The piezoelectric element 410 has a fast response speed and high precision, enabling precise control of the position of the external resonant cavity 300, thereby reducing noise and improving the stability of the low-noise semiconductor laser. By setting the sliding ball 420 and the guide groove 430, the frictional resistance of the external resonant cavity 300 during movement is reduced, improving the reliability of the low-noise semiconductor laser.

[0057] Furthermore, in one embodiment, the low-noise semiconductor laser also includes a displacement detection element and a controller. The displacement detection element is disposed on the substrate 100 and is used to detect the movement stroke of the external resonant cavity 300; the controller is electrically connected to the drive assembly and the displacement detection element.

[0058] In one embodiment, the controller is electrically connected to the displacement detection element and the drive circuit. In one embodiment, the displacement detection element is configured as a Hall effect sensor, and the external resonant cavity 300 is correspondingly provided with a magnetic element. When the external resonant cavity 300 moves, the change in position of the magnetic element causes a change in the magnetic field strength. The Hall effect sensor outputs different voltage signals corresponding to different magnetic field strengths, and the controller receives the voltage signals and controls the drive circuit according to the voltage signals. In another embodiment, the displacement detection element is configured as a capacitive displacement sensor, including two parallel electrode plates, one electrode plate is disposed on the substrate 100, and the other electrode plate is disposed on the external resonant cavity 300. When the external resonant cavity 300 moves, the change in distance between the two electrode plates causes a change in the capacitance value, and the controller controls the drive circuit according to the capacitance change signal. Of course, in other embodiments, the displacement detection element may also be configured as a visual sensor or an ultrasonic sensor, etc., and there is no limitation here.

[0059] The technical solution of this utility model embodiment, by setting a displacement detection element and a controller, allows the displacement detection element to monitor the position change of the resonant cavity in real time and feed the detection signal back to the controller. The controller then precisely controls the driving component based on the feedback signal, thereby achieving precise control of the position of the external resonator and improving the reliability of the low-noise semiconductor laser.

[0060] Please see Figure 1 and Figure 2 In one embodiment, the external resonant cavity 300 is configured as a ring cavity.

[0061] On the one hand, the annular cavity allows the optical signal to be reflected multiple times within the cavity. When the optical signal propagates within the cavity, only signals that meet specific phase conditions can remain stable and accumulate continuously. This process of multiple cyclic reflections automatically filters out optical signals with highly consistent wavelengths, thus significantly improving the monochromaticity of the optical signal. On the other hand, the annular cavity can effectively suppress noise accumulation. Because the optical signal circulates multiple times within the annular cavity, only optical signals with consistent phases can remain stable, while noise signals, due to inconsistent phases, gradually attenuate during these multiple cycles. This phase selection mechanism results in a lower noise level in the output laser. The size of the annular cavity can be flexibly set according to actual needs, and the selection of specific phases of the optical signal can also be flexibly set according to the size of the annular cavity; no limitations are imposed here. Of course, in other embodiments, the external resonant cavity 300 can also be configured as a rectangular cavity or a linear cavity, etc.; no limitations are imposed here.

[0062] In one embodiment, the external resonant cavity 300 includes a first substrate 310, an isolation layer 320, and a ring waveguide 330. The first substrate 310 is movably disposed on the substrate 100, and the driving component is drivenly connected to the first substrate 310; the isolation layer 320 covers the first substrate 310; the ring waveguide 330 is disposed on the side of the isolation layer 320 away from the first substrate 310, and the ring waveguide 330 forms a ring cavity, with an entrance on the side of the ring waveguide 330 near the emitting surface 241.

[0063] Specifically, in one embodiment, the first substrate 310 provides support and mounting base for the external resonant cavity 300. A sliding ball bearing 420 is provided on the side of the first substrate 310 facing away from the isolation layer 320, and the end of the first substrate 310 away from the semiconductor gain medium 200 is connected to the piezoelectric sheet 410. The material of the first substrate 310 can be silicon, metal, or a crystalline material, which has good mechanical strength and thermal conductivity; there is no limitation on this. In one embodiment, the isolation layer 320 is configured as a silicon dioxide thin film covering the first substrate 310, providing optical isolation and preventing interaction between the optical signal and the first substrate 310. In one embodiment, the ring structure of the ring waveguide 330 forms a closed optical path. When the optical signal propagates in the ring waveguide 330, it will be reflected and propagated multiple times in the ring structure, forming a resonance effect. The material of the ring waveguide 330 can be silicon nitride or silicon, which has high refractive index and low optical loss; there is no limitation on this. Furthermore, in one embodiment, the surface of the ring waveguide 330 is coated with an anti-reflection film to further reduce the reflection loss of the optical signal and improve the performance of the external resonant cavity 300. The dimensions of the first substrate 310, the isolation layer 320, and the ring waveguide 330 can all be flexibly set according to actual needs, and are not limited here.

[0064] Furthermore, in one embodiment, the external resonant cavity 300 further includes a coupling waveguide 340, located at the entrance and with a gap between it and the ring waveguide 330. The coupling waveguide 340 guides the optical signal transmission between the semiconductor gain medium 200 and the ring waveguide 330. The gap between the coupling waveguide 340 and the ring waveguide 330 can be flexibly set according to actual needs and is not limited here. In one embodiment, the ring waveguide 330 has a groove on the side near the emitting surface 241, and the coupling waveguide 340 is located in the groove and opposite to the emitting surface 241. In one embodiment, the coupling waveguide 340 is an arc-shaped structure to match the ring waveguide 330. Of course, in other embodiments, the coupling waveguide 340 can also be a rectangular structure or a trapezoidal structure, etc., and is not limited here. The material of the coupling waveguide 340 can be configured as a high-refractive-index material such as silicon nitride, zinc sulfide, or silicon germanium to reduce optical signal loss, and is not limited here.

[0065] The technical solution of this embodiment of the invention, by configuring the external resonant cavity 300 as a ring cavity, better confines the optical field, reduces the scattering and loss of the optical signal within the cavity, thereby reducing noise. The external resonant cavity 300 is layered to better control the propagation path of the optical signal within it, reducing scattering loss during propagation and improving its stability. By incorporating the coupling waveguide 340, a smooth transition and efficient coupling of the optical signal between the external resonant cavity 300 and the semiconductor gain medium 200 are ensured, improving the reliability of the low-noise semiconductor laser.

[0066] Please see Figure 2 In one embodiment, the semiconductor gain medium 200 includes a second substrate 210, a lower confinement layer 230, an active region 240, an upper confinement layer 250, a contact layer 260 and an electrode layer 270 stacked in sequence. The second substrate 210 is disposed on the substrate 100, and the active region 240 has an emission surface 241 at one end near the external resonant cavity 300.

[0067] Electrode layer 270 injects current into active region 240 through contact layer 260, active region 240 generates optical signal, upper confinement layer 250 and lower confinement layer 230 restrict the propagation of optical signal in vertical direction, so that optical signal is emitted from emitting surface 241.

[0068] In one embodiment, an anti-reflective coating is provided at one end of the active region 240 near the external resonant cavity 300, forming an emitting surface 241. Further, in one embodiment, a reflective coating is provided at the other ends of the active region 240, forming a non-reflective surface to prevent optical signal leakage. Of course, in other embodiments, the emitting surface 241 can also be configured as an anti-reflective film or a multilayer anti-reflective dielectric layer, and the non-emitting surface 241 can be configured as an absorbing coating, etc., without limitation. Specifically, in one embodiment, the material of the active region 240 can be indium gallium arsenide and aluminum gallium arsenide, or a mixture of indium gallium arsenide and indium gallium arsenide phosphide, etc., to facilitate the generation of optical signals, without limitation. In one embodiment, the materials of the upper confinement layer 250 and the lower confinement layer 230 can both be high-refractive-index materials such as aluminum gallium arsenide or indium gallium arsenide phosphide, to confine the propagation of optical signals within the active region 240, without limitation. In one embodiment, the contact layer 260 may be made of a material that matches the material of the active region 240, such as gallium arsenide, indium phosphide, or silicon, to provide good electrical contact, reduce resistance, and ensure efficient current injection from the electrode layer 270 into the active region 240. No limitation is imposed here. In one embodiment, the second substrate 210 may be made of a material that matches the material of the active region 240, such as gallium arsenide, indium phosphide, or silicon, to provide good thermal conductivity, prevent heat accumulation, and ensure the stability of the semiconductor gain medium 200 during operation.

[0069] Please see Figure 2 In one embodiment, the semiconductor gain medium 200 further includes a buffer layer 220 disposed between the second substrate 210 and the lower confinement layer 230. In one embodiment, the material of the buffer layer 220 can be aluminum gallium arsenide, indium gallium arsenide, or silicon germanium, which are compatible with the material of the second substrate 210; no limitation is placed here. The dimensions of each layer can be flexibly set according to actual needs; no limitation is placed here either. Thus, the buffer layer 220 can significantly improve the lattice matching and thermal matching between the second substrate 210 and the active region 240, improve the crystal quality of the semiconductor gain medium 200, and thereby further reduce the noise of the low-noise semiconductor laser.

[0070] In one embodiment, the active region 240 is configured as a quantum well structure. The main function of the quantum well structure is to improve gain efficiency through quantum confinement effects. Specifically, in one embodiment, the quantum well structure includes multiple quantum wells arranged equidistantly. In one embodiment, the number of quantum wells is greater than or equal to 5 and less than or equal to 7 to provide sufficient gain without significantly increasing complexity. Of course, in other embodiments, the number of quantum wells can be flexibly set according to actual needs, and is not limited here. Thus, by setting the quantum well structure, the gain efficiency of the semiconductor gain medium 200 can be improved, enabling the optical signal to achieve high gain with lower current injection, thereby improving the overall performance of the low-noise semiconductor laser.

[0071] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A low-noise semiconductor laser, characterized in that, include: substrate; A semiconductor gain medium is disposed on the substrate, and the semiconductor gain medium is used to generate optical signals; An external resonant cavity is movably disposed on the substrate, and the entrance of the external resonant cavity is opposite to the emission surface of the semiconductor gain medium; as well as, A driving component is disposed on the substrate and driven to connect to the external resonant cavity, such that the external resonant cavity moves relative to the substrate to move closer to or further away from the emitting surface.

2. The low-noise semiconductor laser as described in claim 1, characterized in that, The driving component includes: A piezoelectric element is connected at one end to the external resonant cavity and at the other end to the substrate. The deformation of the piezoelectric element drives the external resonant cavity to move closer to or away from the emitting surface.

3. The low-noise semiconductor laser as described in claim 1, characterized in that, The driving component also includes: A sliding ball bearing is movably positioned on the side of the external resonant cavity facing the substrate; and, A guide groove is provided on the substrate, and the sliding ball is tactilely connected to the guide groove.

4. The low-noise semiconductor laser as described in claim 1, characterized in that, The low-noise semiconductor laser also includes: A displacement detection element is disposed on the substrate, the displacement detection element being used to detect the movement stroke of the external resonant cavity; and, The controller is electrically connected to the drive assembly and the displacement detection element.

5. The low-noise semiconductor laser as described in claim 1, characterized in that, The external resonant cavity is configured as a ring cavity.

6. The low-noise semiconductor laser as described in claim 5, characterized in that, The external resonant cavity includes: A first substrate is movably disposed on the substrate, and the driving component is drivingly connected to the first substrate; An isolation layer covering the first substrate; and, A ring waveguide is disposed on the side of the isolation layer away from the first substrate, the ring waveguide forming the ring cavity, and the entrance is provided on the side of the ring waveguide near the emitting surface.

7. The low-noise semiconductor laser as described in claim 6, characterized in that, The external resonant cavity also includes: A coupling waveguide is provided at the entrance and has a gap between it and the ring waveguide. The coupling waveguide is used to guide the optical signal to transmit between the semiconductor gain medium and the ring waveguide.

8. The low-noise semiconductor laser as described in claim 1, characterized in that, The semiconductor gain medium includes a second substrate, a lower confinement layer, an active region, an upper confinement layer, a contact layer, and an electrode layer stacked in sequence. The second substrate is disposed on the substrate, and the active region has an emission surface at one end near the external resonant cavity.

9. The low-noise semiconductor laser as described in claim 8, characterized in that, The semiconductor gain medium further includes: A buffer layer is disposed between the second substrate and the lower limiting layer.

10. The low-noise semiconductor laser as described in claim 8, characterized in that, The active region is configured as a quantum well structure.

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