Dual-fp coupled cavity laser device and electronic device

Abstract

Embodiments of the present application provide a double FP coupling cavity laser device and an electronic device, comprising: a first laser, the first laser having a first whispering gallery microcavity; a second laser, the second laser having a second whispering gallery microcavity; a first FP cavity, the first FP cavity being connected with the first whispering gallery microcavity; a second FP cavity, the second FP cavity being connected with the second whispering gallery microcavity; a branch waveguide, the branch waveguide having a first waveguide and a second waveguide, the first waveguide being connected with the first FP cavity, the second waveguide being connected with the second FP cavity; a coupler, the coupler being connected with the first waveguide and the second waveguide and outputting the spectrum of the first waveguide and the second waveguide after coupling; the length of the first FP cavity and the second FP cavity in a first direction is different. By setting the first FP cavity and the second FP cavity with different lengths, in combination with the synergistic effect of the branch waveguide and the coupler, the laser mode stability is effectively improved and the structure is simplified, and the advantages of precise spectrum regulation, simple preparation process are possessed.

Description

Technical Field

[0001] This application relates to the technical field of lasers, and more particularly to a dual-FP coupled-cavity laser device and electronic equipment. Background Technology

[0002] Semiconductor lasers have been widely used in many fields such as optical communication, optical sensing, and laser processing due to their advantages such as small size, high efficiency, and ease of integration. With the continuous development of technology, the performance requirements for semiconductor lasers are also becoming more and more demanding, such as narrow linewidth, high power, and single-mode output.

[0003] Traditional Fabry-Perot (FP) lasers, while simple in structure, suffer from wide linewidths and poor mode selectivity, making them unsuitable for some high-precision applications. To improve laser performance, related technologies employ coupled-cavity structures, coupling multiple cavities together to achieve precise wavelength control and linewidth narrowing using the vernier effect. However, existing coupled-cavity structures are complex, difficult to fabricate, and their mode stability is not ideal, making them susceptible to external environmental factors. In particular, for lasers with dual FP cavities, precise coupling control between the two FP cavities is challenging, leading to unstable laser output modes and difficulty in accurately controlling spectral characteristics. Furthermore, existing dual FP cavity lasers have structural design flaws that fail to effectively address the optical field coupling problem between the two FP cavities, resulting in low laser efficiency.

[0004] Therefore, there is an urgent need for a dual-FP coupled-cavity laser device with a simple coupled-cavity structure, simple fabrication process, and stable mode of coupled-cavity laser. Summary of the Invention

[0005] This application provides a dual-FP coupled-cavity laser device and electronic device. The coupled-cavity structure is simple, the fabrication process is simple, and the mode of the coupled-cavity laser is stable.

[0006] In a first aspect, embodiments of this application provide a dual-FP coupled-cavity laser device, comprising:

[0007] A first laser having a first whispering-gallery microcavity;

[0008] A second laser having a second whispering-gallery microcavity;

[0009] The first FP cavity is connected to the first whispering wall microcavity;

[0010] The second FP cavity is connected to the second whispering wall microcavity;

[0011] A branched waveguide, wherein the branched waveguide has a first waveguide and a second waveguide, the first waveguide being connected to the first FP cavity, and the second waveguide being connected to the second FP cavity;

[0012] A coupler, which is connected to a first waveguide and a second waveguide and outputs the spectra of the first waveguide and the second waveguide after coupling;

[0013] The lengths of the first FP cavity and the second FP cavity along the first direction are different.

[0014] In one possible implementation, this application also proposes that the length of the first FP cavity along the first direction is greater than the length of the second FP cavity along the first direction.

[0015] In one possible implementation, this application also proposes that the interval between the first FP cavity and the second FP cavity along the second direction is greater than or equal to 200 μm and less than or equal to 300 μm.

[0016] In one possible implementation, this application also proposes that a first P-surface electrode is disposed on the first sounding wall microcavity, a second P-surface electrode is disposed on the second sounding wall microcavity, a third P-surface electrode is disposed on the first FP cavity, a fourth P-surface electrode is disposed on the second FP cavity, a first electrical isolation groove is disposed between the first P-surface electrode and the third P-surface electrode, and a second electrical isolation groove is disposed between the second P-surface electrode and the fourth P-surface electrode.

[0017] In one possible implementation, this application also proposes to include:

[0018] The N-face electrode has a first whispering-gallery microcavity disposed on the N-face electrode and a second whispering-gallery microcavity disposed on the N-face electrode.

[0019] In one possible implementation, this application also proposes that the length of the first waveguide along the first direction is less than the length of the second waveguide along the first direction, and the length of the first waveguide along the second direction is less than the length of the second waveguide along the second direction.

[0020] In one possible implementation, this application also proposes that the spacing between the first waveguide and the second waveguide along the second direction is greater than or equal to 200 μm and less than or equal to 300 μm.

[0021] In one possible implementation, this application also proposes that the orthographic projection shape of the first and second whispering-gallery microcavities onto the N-plane electrode is square.

[0022] In one possible implementation, this application also proposes that the first sounding-gallery microcavity has a first protruding ridge connected to the end face of the first FP cavity, and the second sounding-gallery microcavity has a second protruding ridge connected to the end face of the second FP cavity.

[0023] Secondly, embodiments of this application also provide an electronic device, including the aforementioned dual FP-coupled cavity laser device.

[0024] This application provides a dual-FP coupled-cavity laser device and electronic device. By setting a first FP cavity and a second FP cavity with different lengths, and combining the synergistic effect of the branch waveguide and the coupler, the laser mode stability is effectively improved and the structure is simplified. It has the advantages of precise spectral control and simple fabrication process. Attached Figure Description

[0025] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0026] Figure 1 This is a partial structural schematic diagram of a reflector according to this application;

[0027] Figure 2 This is a schematic diagram of the overall structure of a reflector according to this application.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1. First whispering-gallery microcavity; 2. Second whispering-gallery microcavity; 3. First P-plane electrode; 4. Second P-plane electrode; 5. Third P-plane electrode; 6. Fourth P-plane electrode; 7. First FP cavity; 8. Second FP cavity; 9. First electrical isolation trench; 10. Second electrical isolation trench; 11. First waveguide; 12. Second waveguide; 13. Coupler; 14. N-plane electrode.

[0030] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0031] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0032] In related technologies, semiconductor lasers are widely used due to their small size and high efficiency. However, traditional Fabry-Perot lasers (FP lasers) suffer from wide linewidths and poor mode selectivity. While existing coupled-cavity structures can improve performance through the vernier effect, their complex structures and difficult fabrication processes result in insufficient mode stability. For example, in scenarios requiring high-precision laser output, complex coupled-cavity structures are easily affected by environmental factors, impacting the reliability and stability of the laser.

[0033] Therefore, by setting up a first FP cavity 7 and a second FP cavity 8 with different lengths, and combining the synergistic effect of the branch waveguide and the coupler 13, this application ensures the reliability and stability of the laser.

[0034] The technical solution of this application and how it solves the above-mentioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings. (For ease of description, the X direction is defined as the first direction, and the Y direction as the second direction.)

[0035] Reference Figure 1 This application discloses a dual-FP coupled-cavity laser device, comprising a first laser and a second laser. The first laser has a first whispering-gallery microcavity 1, and the second laser has a second whispering-gallery microcavity 2. The first FP cavity 7 is connected to the first whispering-gallery microcavity 1, and the second FP cavity 8 is connected to the second whispering-gallery microcavity 2. The branch waveguide includes a first waveguide 11 and a second waveguide 12, the first waveguide 11 is connected to the first FP cavity 7, and the second waveguide 12 is connected to the second FP cavity 8. The coupler 13 is connected to the first waveguide 11 and the second waveguide 12 and outputs the spectra of the two after spectral coupling. The first FP cavity 7 and the second FP cavity 8 have different lengths along a first direction.

[0036] Among them, the whispering-gallery microcavity is a microcavity with a ring resonant structure. It can be formed by etching semiconductor materials to form a ring waveguide structure, which is used to enhance optical field confinement and feedback.

[0037] An FP cavity is a resonant cavity composed of two reflective surfaces, which can be implemented using end-face reflection of semiconductor materials or a distributed Bragg reflector to generate specific resonant modes. Specifically, the first FP cavity 7 is an open optical resonant structure connected to the first whispering-gallery microcavity 1, and the length of the first FP cavity 7 along the first direction determines the free spectral range of the cavity. The second FP cavity 8 is an open optical resonant structure connected to the second whispering-gallery microcavity 2, and the length of the second FP cavity 8 along the first direction is set to be shorter than that of the first FP cavity 7.

[0038] A branched waveguide is a waveguide structure for splitting optical signals, used to separate the optical path into different FP cavities.

[0039] Coupler 13 is a device for combining optical signals. It can be a multimode interference coupler 13 or a directional coupler 13, used to superimpose the spectra output from different FP cavities.

[0040] The length difference between the first FP cavity 7 and the second FP cavity 8 along the first direction achieves pattern filtering through the vernier effect, thereby narrowing the linewidth.

[0041] Specifically, the first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 are connected to the first FP cavity 7 and the second FP cavity 8, respectively, forming independent optical feedback paths. The optical signal enters the FP cavities of different lengths through the first waveguide 11 and the second waveguide 12 of the branch waveguide, generating different resonant modes. Because the two FP cavities have different lengths, their resonant peak spacing differs. The coupler 13 superimposes the spectra of the two FP cavities and suppresses non-target modes through the vernier effect, ultimately outputting a narrow-linewidth laser.

[0042] For example, when the length of the first FP cavity 7 is relatively long, its free spectral range is small, which forms a periodic suppression with the resonant peak interval of the second FP cavity 8, thereby achieving single-mode selection.

[0043] Compared to related technologies, traditional coupled-cavity lasers require complex multi-stage waveguides or external filters to achieve mode selection. This application simplifies the optical path structure by directly connecting two FP cavities to a whispering-gallery microcavity. Furthermore, the combination of the branch waveguide and coupler 13 avoids additional mode control components, reducing fabrication complexity. In related technologies, the stability of the coupled cavity depends on precise alignment, while this application reduces external interference factors through a monolithic integrated design.

[0044] Through the above technical solution, this application realizes a simplified dual-FP coupled-cavity laser device. The vernier effect is generated by using FP cavities of different lengths, effectively narrowing the linewidth and improving mode stability. The integrated design of the branch waveguide and coupler 13 reduces optical path complexity, while the monolithic integration process enhances device reliability, making it suitable for applications with high requirements for laser linewidth and stability.

[0045] Reference Figure 2 This application further proposes that the length of the first FP cavity 7 along the first direction is greater than the length of the second FP cavity 8 along the first direction.

[0046] Specifically, the first FP cavity 7 and the second FP cavity 8 are connected to the corresponding first whispering-gallery microcavity 1 and second whispering-gallery microcavity 2 via branch waveguides. When there is a difference in length between the first FP cavity 7 and the second FP cavity 8 along the first direction, their free spectral ranges shift. During spectral coupling at coupler 13, the vernier effect principle allows only the light field within a specific wavelength range to resonate and enhance, while other wavelengths are suppressed due to phase mismatch. This design causes the resonant modes of the first FP cavity 7 and the second FP cavity 8 to form an interleaved distribution in the frequency domain, thereby enhancing mode selectivity.

[0047] Compared with related technologies, traditional coupled-cavity lasers typically employ symmetrical or complex tuning structures to achieve mode control. However, this application achieves mode screening simply by adjusting the waveguide etching dimensions during fabrication through an asymmetric FP cavity length design, without the need to introduce additional tuning elements or complex coupling structures. This significantly simplifies the fabrication process and reduces environmental sensitivity.

[0048] Through the above technical solution, this application can effectively suppress multi-longitudinal-mode oscillations, enhance the single-mode stability of the laser output spectrum, and avoid insertion loss and process errors introduced by complex coupling structures. It is suitable for optical communication systems with high requirements for narrow linewidth and wavelength stability.

[0049] Reference Figure 2 This application further proposes that the spacing between the first FP cavity 7 and the second FP cavity 8 along the second direction is greater than or equal to 200 μm and less than or equal to 300 μm.

[0050] For example, the spacing between the first FP cavity 7 and the second FP cavity 8 along the second direction can be 200μm, 250μm or 300μm, etc. The embodiments of this application do not limit this, nor are they limited to the above example.

[0051] Specifically, when the spacing between the first FP cavity 7 and the second FP cavity 8 in the second direction is controlled to be between 200 μm and 300 μm, a stable phase-matching condition can be formed in the optical field coupling region of the two cavities. Within this range, when the optical field output from the first FP cavity 7 is transmitted to the second FP cavity 8 through the branch waveguide, its evanescent wave penetration depth and the spacing distance form a complementary relationship, thereby suppressing the excitation of higher-order modes. At the same time, this spacing range can avoid optical field energy loss due to excessively close distance or decreased coupling efficiency due to excessively large distance.

[0052] Through the above technical solution, this application effectively solves the mode instability problem caused by improper cavity spacing in dual FP cavity lasers, enabling the coupled cavity structure to adapt to process deviations in mass production while ensuring single-mode output, thereby improving the yield and reliability of the device.

[0053] Reference Figure 2This application further proposes that a first P-surface electrode 3 is provided on the first sounding wall microcavity 1, a second P-surface electrode 4 is provided on the second sounding wall microcavity 2, a third P-surface electrode 5 is provided on the first FP cavity 7, a fourth P-surface electrode 6 is provided on the second FP cavity 8, a first electrical isolation groove 9 is provided between the first P-surface electrode 3 and the third P-surface electrode 5, and a second electrical isolation groove 10 is provided between the second P-surface electrode 4 and the fourth P-surface electrode 6.

[0054] Among them, the P-side electrode is a metal contact layer located on the surface of the P-type doped layer of the semiconductor material. It can be implemented using a titanium / platinum / gold stacked structure and is used to inject charge carriers into the laser.

[0055] Electrically isolated trenches are physical isolation structures formed through etching processes. They can be formed by dry etching to create trenches that penetrate deep into the P-type layer, thereby blocking current diffusion between adjacent electrodes.

[0056] Specifically, the first P-side electrode 3 and the second P-side electrode 4 respectively cover the top regions of the corresponding first whispering-gallery microcavities 1 and 1, controlling the gain characteristics of their respective microcavities through independent current injection. The third P-side electrode 5 and the fourth P-side electrode 6 respectively cover the end regions of the corresponding first FP cavity 7 and 8, forming current injection paths with the corresponding microcavities. The first electrical isolation groove 9 is located at the junction of the first P-side electrode 3 and the third P-side electrode 5, and the second electrical isolation groove 10 is located at the junction of the second P-side electrode 4 and the fourth P-side electrode 6. By physically isolating the electrodes, the lateral leakage current between them is blocked, making the current injection paths of each electrode independent and avoiding mode interference caused by carrier diffusion.

[0057] Compared to related technologies, traditional coupled-cavity lasers typically employ a shared electrode structure, leading to current crosstalk between different cavities. This application, through independent electrodes combined with an isolation trench structure, achieves independent tuning of multiple cavities while effectively suppressing leakage current between adjacent electrodes, thus solving the mode instability problem caused by current diffusion in traditional structures.

[0058] Through the above technical solution, this application achieves precise current control in each functional region of a dual-FP coupled-cavity laser device, avoiding electrical crosstalk between different cavities and improving the stability of the laser mode. The electrode isolation structure effectively reduces non-radiative recombination loss, enabling the laser to achieve higher photoelectric conversion efficiency while maintaining narrow linewidth output.

[0059] Reference Figure 2 This application further proposes a dual FP-coupled cavity laser device, which also includes an N-face electrode 14, a first whispering-gallery microcavity 1 disposed on the N-face electrode 14, and a second whispering-gallery microcavity 2 disposed on the N-face electrode 14.

[0060] Among them, the N-face electrode 14 refers to the common electrode formed on the surface of the N-type semiconductor layer opposite to the P-type semiconductor layer in the semiconductor laser structure. It can be made of metal material through evaporation or sputtering process and is used to provide a unified current injection path for the laser.

[0061] The first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 are respectively disposed on the N-side electrode 14, so that the first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 are directly fabricated on the N-type semiconductor material substrate. Specifically, a ring waveguide structure with total internal reflection characteristics can be formed by photolithography and etching processes, so that the light wave forms a stable whispering-gallery mode in the microcavity.

[0062] Specifically, an N-face electrode layer 14 is formed on the surface of an N-type semiconductor substrate through ion implantation or epitaxial growth. The annular waveguide structures of the first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 are directly formed on the surface of this electrode layer through an etching process. The first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 share the same N-face electrode 14 as a common terminal for current injection. Synchronous pumping of the two cavities is achieved by controlling the independent bias voltage of the corresponding P-face electrodes. Since the first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 adopt an integrated structure with the electrode layer, the parasitic capacitance and impedance mismatch problems caused by independent electrode leads in traditional technologies are avoided.

[0063] Compared to related technologies, traditional coupled-cavity lasers typically require a separate N-face electrode 14 for each resonant cavity, resulting in complex device structures and electromagnetic interference between electrodes. This application achieves synchronous current injection in both cavities by sharing the N-face electrode 14, which not only simplifies the electrode layout but also eliminates signal delay differences between multiple electrodes, thereby improving mode stability.

[0064] Through the above technical solutions, this application effectively solves the problems of complex laser structure and mode instability caused by discrete electrodes. By sharing the N-face electrode 14, the fabrication difficulty of the device is reduced, while ensuring the phase consistency of the dual-cavity pump signal. This enables the coupled-cavity laser to achieve higher mode stability and anti-interference capability while maintaining single-mode output.

[0065] Reference Figure 2 This application further proposes that the length of the first waveguide 11 along the first direction is less than the length of the second waveguide 12 along the first direction, and the length of the first waveguide 11 along the second direction is less than the length of the second waveguide 12 along the second direction.

[0066] Specifically, by making the lengths of the first waveguide 11 smaller than those of the second waveguide 12 in both the axial and lateral directions, differentiated optical propagation characteristics can be formed in the two waveguide paths. When the optical signals from the first waveguide 11 and the second waveguide 12 interfere through the coupler 13, the difference in axial length affects the longitudinal optical path difference, while the difference in lateral length affects the lateral mode distribution. This dual-dimensional dimensional difference can produce a composite phase modulation effect, enhancing mode selection characteristics during coupling while avoiding mode degeneracy that may result from single-dimensional adjustment.

[0067] Compared to related technologies, traditional coupled-cavity structures typically employ symmetrical waveguide designs or single-dimensional size adjustments, which can easily lead to insufficient phase matching or intensified mode competition. This application achieves multi-dimensional phase modulation capabilities while maintaining structural compactness through a dual-dimensional asymmetric waveguide design. Compared to equal-length waveguide structures, this differentiated combination of waveguide dimensions can more effectively extend the free spectral range and enhance the mode selection mechanism.

[0068] Through the above technical solution, this application can effectively suppress multimode oscillation and improve the single-mode stability of the laser. The composite phase difference generated by the two-dimensional waveguide difference can enhance the mode discrimination capability, automatically filter higher-order modes during coupling, and ensure the purity of the output spectrum. At the same time, this structure can achieve mode control without introducing complex external cavity components, which is beneficial to the miniaturization and integrated manufacturing of the device.

[0069] Reference Figure 2 This application further proposes that the interval between the first waveguide 11 and the second waveguide 12 along the second direction is greater than or equal to 200 μm and less than or equal to 300 μm.

[0070] For example, the interval between the first waveguide 11 and the second waveguide 12 along the second direction can be 200μm, 250μm or 300μm, etc. The embodiments of this application do not limit this, nor are they limited to the above examples.

[0071] Specifically, when the spacing between the first waveguide 11 and the second waveguide 12 in the second direction is within this range, the evanescent wave coupling strength formed between the two waveguides is controlled to achieve effective spectral coupling while avoiding mode competition between adjacent waveguides. During optical field transmission, the limited spacing between the first waveguide 11 and the second waveguide 12 ensures that the two optical signals received by the coupler 13 have a matched phase relationship, while reducing unintended mode coupling or thermal crosstalk caused by excessive spacing. Establishing a stable coupling strength threshold within the process tolerance range avoids thermal crosstalk deterioration caused by excessive spacing and prevents insufficient coupling efficiency caused by excessive spacing, thereby improving the working stability of the laser.

[0072] Through the above technical solution, this application effectively suppresses the mode instability problem caused by improper waveguide spacing in dual FP cavity lasers, ensures that the synthesized spectrum output by coupler 13 has a single dominant mode, and reduces the sensitivity of the fabrication process to device performance, providing a reliable narrow linewidth light source for high-precision optical communication systems.

[0073] Reference Figure 2 This application further proposes that the orthographic projection shape of the first whispering glide microcavity 1 and the second whispering glide microcavity 2 onto the N-plane electrode 14 is square.

[0074] The square shape of the orthogonal projection onto the N-face electrode 14 means that the projection outlines of the first whispering microcavity 1 and the second whispering microcavity 2 in the direction perpendicular to the N-face electrode 14 are square. This shape helps to improve the uniformity of the electrode contact area and at the same time reduce the alignment error between the microcavity edge and the electrode.

[0075] Specifically, the square projections of the first whispering-gallery microcavity 1 and the second whispering-gallery microcavity 2 onto the N-face electrode 14 create a regular symmetrical structure at the contact surface between the microcavity and the electrode. During laser operation, the symmetrical characteristics of the square projection reduce current distribution differences caused by uneven electrode contact, thereby suppressing mode hopping. Furthermore, the square contour is easier to achieve using a standard rectangular mask in photolithography, avoiding processing errors at complex curved edges, and thus improving the alignment accuracy between the microcavity and the electrode.

[0076] Compared to related technologies, existing whispering-gallery microcavities often employ circular or elliptical projections. These shapes are prone to mask alignment deviations during photolithography due to variations in edge curvature, which in turn affects electrode contact uniformity. This application simplifies the fabrication process by employing a square projection, leveraging the predictability of its straight boundaries, while simultaneously enhancing current injection stability through geometric symmetry.

[0077] Through the above technical solution, this application can improve the contact uniformity between the whispering galvanic microcavity and the N-face electrode 14, reduce the process complexity, thereby improving the mode stability of the laser and reducing alignment errors in the fabrication process.

[0078] Reference Figure 2 This application further proposes that the first sounding wall microcavity 1 has a first protruding ridge, which is connected to the end face of the first FP cavity 7, and the second sounding wall microcavity 2 has a second protruding ridge, which is connected to the end face of the second FP cavity 8.

[0079] The connection between the first protruding ridge and the end face of the first FP cavity 7, and the connection between the second protruding ridge and the end face of the second FP cavity 8, can enhance the optical field coupling efficiency between the microcavity and the FP cavity.

[0080] End face connection refers to the physical contact between the side edge of the protrusion near the corner and the end face of the corresponding FP cavity, so that the light field can be directly injected into the FP cavity through the protrusion.

[0081] Specifically, the convex ridge structure extends to the end face of the corresponding FP cavity to form direct contact. When the whispering-gallery mode optical field in the whispering-gallery microcavity propagates along the circumference of the microcavity, part of the optical field is directly coupled into the FP cavity through the convex ridge structure. Due to the waveguide effect of the convex ridge, the optical field maintains mode matching during transmission, avoiding the mode mismatch loss present in traditional end-face coupling.

[0082] Compared with related technologies, traditional coupling methods often employ tapered waveguides or grating couplers 13 to couple microcavities to FP cavities, requiring complex three-dimensional structure fabrication. This application achieves direct end-face coupling through the convex ridge structure of the microcavity body, which not only simplifies the fabrication process but also avoids the additional losses introduced by the coupler 13. The convex ridge structure maintains the continuity of the optical field mode, solving the mode-jumping problem caused by coupling structure mismatch in traditional schemes.

[0083] Through the above technical solution, this application achieves efficient optical coupling between the whispering-gallery microcavity and the FP cavity, improving coupling efficiency. The directional guidance characteristics of the convex ridge structure effectively suppress stray mode coupling, improve the side-mode suppression ratio of the laser, and the direct end-face contact coupling method relaxes assembly tolerance limits and significantly reduces the difficulty of packaging process.

[0084] Reference Figure 2 This application further proposes an electronic device including the aforementioned dual FP-coupled cavity laser device. The laser has a first laser, a second laser, a first FP cavity 7, a second FP cavity 8, a branch waveguide, and a coupler 13. The first laser and the second laser each have a whispering-gallery microcavity. The first FP cavity 7 is connected to the first whispering-gallery microcavity 1, and the second FP cavity 8 is connected to the second whispering-gallery microcavity 2. The branch waveguide includes a first waveguide 11 and a second waveguide 12. The first waveguide 11 is connected to the first FP cavity 7, and the second waveguide 12 is connected to the second FP cavity 8. The coupler 13 couples the spectra of the first waveguide 11 and the second waveguide 12 and outputs them. The first FP cavity 7 and the second FP cavity 8 have different lengths along a first direction.

[0085] A dual FP-coupled cavity laser device refers to a laser structure containing two Fabry-Perot cavities. Specifically, it can be implemented by coupling FP cavities of different lengths with whispering-gallery microcavities, and wavelength selection and linewidth narrowing can be achieved through the vernier effect.

[0086] Electronic devices are terminal devices that integrate the laser. They can be, but are not limited to, optical communication modules or optical sensing devices, and can achieve signal transmission or detection functions through the narrow linewidth spectrum output by the laser.

[0087] Specifically, the electronic device integrates a dual-FP-coupled-cavity laser device. Utilizing the coupling between its two FP cavities of different lengths and corresponding whispering-gallery microcavities, it generates two independently transmitted optical signals in a branch waveguide. When the two optical signals pass through coupler 13, their spectra exhibit a vernier effect due to the difference in FP cavity lengths, ultimately outputting a narrow-linewidth single-mode laser. This laser, as a light source for the electronic device, can be directly applied to the signal transmission module of an optical communication system or the detection unit of an optical sensing system, without the need for additional complex optical filtering or frequency stabilization devices.

[0088] Compared with related technologies, existing electronic devices typically use a single FP-cavity laser or external filter components, which suffer from problems such as wide linewidth and insufficient mode stability. In contrast, this application utilizes a built-in dual FP-coupled cavity structure and the vernier effect generated by the cavity length difference to directly achieve spectral screening and linewidth compression inside the device. This avoids the size limitations of external devices and reduces the risk of spectral drift caused by environmental disturbances.

[0089] Through the above technical solution, this application can provide electronic devices with highly stable narrow linewidth laser output, solve the problem of signal distortion or decreased detection accuracy caused by excessively wide linewidth in traditional laser light sources, and at the same time simplify the complexity of the optical system and improve the working reliability of the equipment in high temperature or vibration environments.

[0090] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A dual-FP coupled-cavity laser device, characterized in that, include: A first laser having a first whispering-gallery microcavity; A second laser having a second whispering-gallery microcavity; The first FP cavity is connected to the first whispering wall microcavity; The second FP cavity is connected to the second whispering wall microcavity; A branched waveguide, wherein the branched waveguide has a first waveguide and a second waveguide, the first waveguide being connected to the first FP cavity, and the second waveguide being connected to the second FP cavity; A coupler, which is connected to a first waveguide and a second waveguide and outputs the spectra of the first waveguide and the second waveguide after coupling; The lengths of the first FP cavity and the second FP cavity along the first direction are different; A first P-surface electrode is provided on the first whispering wall microcavity, a second P-surface electrode is provided on the second whispering wall microcavity, a third P-surface electrode is provided on the first FP cavity, a fourth P-surface electrode is provided on the second FP cavity, a first electrical isolation groove is provided between the first P-surface electrode and the third P-surface electrode, and a second electrical isolation groove is provided between the second P-surface electrode and the fourth P-surface electrode. The N-face electrode has a first whispering-gallery microcavity disposed on the N-face electrode and a second whispering-gallery microcavity disposed on the N-face electrode.

2. The dual FP-coupled cavity laser device according to claim 1, characterized in that: The length of the first FP cavity along the first direction is greater than the length of the second FP cavity along the first direction.

3. A dual FP-coupled cavity laser device according to claim 2, characterized in that: The distance between the first FP cavity and the second FP cavity along the second direction is greater than or equal to 200 μm and less than or equal to 300 μm.

4. A dual FP-coupled cavity laser device according to any one of claims 1-3, characterized in that: The length of the first waveguide along the first direction is less than the length of the second waveguide along the first direction, and the length of the first waveguide along the second direction is less than the length of the second waveguide along the second direction.

5. A dual FP-coupled cavity laser device according to claim 4, characterized in that: The spacing between the first waveguide and the second waveguide along the second direction is greater than or equal to 200 μm and less than or equal to 300 μm.

6. A dual FP-coupled cavity laser device according to claim 1, characterized in that: The first and second whispering-gallery microcavities have a square shape when projected onto the N-plane electrode.

7. A dual FP-coupled cavity laser device according to claim 6, characterized in that: The first sounding wall microcavity has a first protruding ridge, which is connected to the end face of the first FP cavity. The second sounding wall microcavity has a second protruding ridge, which is connected to the end face of the second FP cavity.

8. An electronic device, characterized in that, Includes the dual FP-coupled cavity laser device as described in any one of claims 1-7 above.

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