Semiconductor microcavity lasers that spontaneously generate nonlinear effects

Abstract

This disclosure provides a semiconductor microcavity laser that spontaneously generates nonlinear effects, comprising: an arc-edged octagonal microcavity configured to generate a hybrid quadrilateral resonant mode through total internal reflection of light from its second-nearest side; a quadrilateral ring electrode formed on the arc-edged octagonal microcavity for decoupling the hybrid quadrilateral resonant mode into a first quadrilateral resonant mode and a second quadrilateral resonant mode, causing the first and second quadrilateral resonant modes to interact and generate a nonlinear effect; and a waveguide for receiving the nonlinear effect generated by the interaction of the two decoupled modes in the arc-edged octagonal microcavity and outputting an optical signal. This semiconductor microcavity laser that spontaneously generates nonlinear effects avoids external disturbances and possesses flexibility and controllability.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor laser technology, and more particularly to a semiconductor microcavity laser that spontaneously generates nonlinear effects. Background Technology

[0002] Nonlinear dynamics in semiconductor lasers have wide applications in secure communication, microwave signal generation, random number generation, and complex photonic information processing networks. These nonlinear dynamic effects mainly include injection-locked loops, four-wave mixing, periodic oscillations, and chaotic states, primarily based on semiconductor lasers and achieved through external optical injection, optical feedback, and photoelectric feedback. In recent years, to promote on-chip photonic integration, optical mutual injection of semiconductor lasers has emerged as a novel method for generating nonlinear effects. Researchers have made significant progress in generating nonlinear dynamics through optical mutual injection in distributed feedback lasers, distributed Bragg reflector lasers, vertical-cavity surface-emitting lasers, and whispering-gallery microcavity lasers. However, these methods are extremely sensitive to external perturbations and require precise control. Therefore, spontaneous generation of nonlinear effects based on independent semiconductor lasers is of significant research importance. Summary of the Invention

[0003] To address the aforementioned technical problems, this disclosure provides a semiconductor microcavity laser that spontaneously generates nonlinear effects, thereby at least partially solving the above-mentioned technical problems.

[0004] Based on this, the present disclosure provides a semiconductor microcavity laser that spontaneously generates nonlinear effects, comprising: an arc-edged octagonal microcavity configured to generate a hybrid quadrilateral resonant mode through total internal reflection of light from the second-nearest side; a quadrilateral ring electrode formed on the arc-edged octagonal microcavity for decoupling the hybrid quadrilateral resonant mode into a first quadrilateral resonant mode and a second quadrilateral resonant mode, such that the first quadrilateral resonant mode and the second quadrilateral resonant mode interact to generate a nonlinear effect; and a waveguide for receiving the nonlinear effect generated by the interaction of the two decoupled modes in the arc-edged octagonal microcavity and outputting an optical signal.

[0005] According to embodiments of this disclosure, the first track corresponding to the first quadrilateral resonant mode and the second track corresponding to the second quadrilateral resonant mode are independent of each other.

[0006] According to an embodiment of this disclosure, the shape of the quadrilateral ring electrode is the same as the shape of one of the first and second tracks.

[0007] According to embodiments of this disclosure, a quadrilateral ring electrode directly excites one of the first quadrilateral resonant modes and the second quadrilateral resonant modes through carrier injection. Under the influence of the overlapping spatial optical field distributions of the first quadrilateral resonant mode and the lateral diffusion of carriers, the first quadrilateral resonant mode and the second quadrilateral resonant mode are lased and interact to produce nonlinear effects.

[0008] According to embodiments of this disclosure, the frequency interval between the first quadrilateral resonant mode and the second quadrilateral resonant mode is adjusted by regulating the charge carriers injected into the quadrilateral ring electrode.

[0009] According to embodiments of this disclosure, the frequency interval between the first quadrilateral resonant mode and the second quadrilateral resonant mode is 10 GHz to 14 GHz.

[0010] According to an embodiment of this disclosure, the waveguide includes a first end face and a second end face. The first end face is directly connected to one of the vertices of the arc-edged octagonal microcavity, and the second end face is a cleavage surface.

[0011] According to embodiments of this disclosure, the waveguide is a strip waveguide.

[0012] According to embodiments of this disclosure, an arc-edge octagonal microcavity and a waveguide are formed on the same epitaxial wafer, the substrate of which is InP and the active layer is an AlGalnAs multi-quantum-well structure.

[0013] According to an embodiment of this disclosure, the arc-edged octagonal microcavity is surrounded by divinylsiloxane bisbenzocyclobutene, which is used to confine the spatial light field formed by the arc-edged octagonal microcavity.

[0014] The semiconductor microcavity laser that spontaneously generates nonlinear effects according to the embodiments of this disclosure has at least the following beneficial effects:

[0015] The resonant cavity of the semiconductor microcavity laser is set as an arc-edge octagonal microcavity structure. Since there is a hybrid quadrilateral resonant mode formed by the coupling of two quadrilateral resonant modes in the arc-edge octagonal microcavity, the hybrid mode is decoupled by designing a quadrilateral ring electrode along the track of one of the resonant modes of the hybrid resonant mode. In this way, nonlinear effects can be spontaneously generated based on the interaction between the two decoupled modes of the independent laser, without the need for complex experimental equipment modulation.

[0016] Furthermore, the two resonant modes of the semiconductor microcavity laser after decoupling can be simultaneously lased and interact due to the diffusion of transverse current. The frequency interval between the two modes can be adjusted by changing the injected charge carriers, thus flexibly controlling the generation of different types of nonlinear effects.

[0017] Furthermore, the first end face is directly connected to one of the vertices of the arc-edged octagonal microcavity. Since the mode field distribution is stronger at the midpoint of each side of the arc-edged octagonal microcavity and weaker at the corners, directly connecting the waveguide at the vertex of the arc-edged octagonal microcavity can both preserve the mode field distribution and ensure the mode quality factor, and achieve directional output.

[0018] Furthermore, the waveguide and cavity are grown on the same epitaxial wafer, the substrate material is InP, the active layer is an AlGalnAs multi-quantum-well structure, and the cavity is surrounded by divinylsiloxane bisbenzocyclobutene, which can effectively reduce the device leakage current.

[0019] In addition, this semiconductor microcavity laser has a simple manufacturing process, low cost, high yield, and is easy to integrate on a chip. Attached Figure Description

[0020] The above and other objects, features and advantages of this disclosure will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0021] Figure 1 A schematic three-dimensional structural diagram of a semiconductor microcavity laser that spontaneously generates nonlinear effects, provided in an embodiment of the present disclosure, is shown.

[0022] Figure 2 A schematic diagram of a semiconductor microcavity laser that spontaneously generates nonlinear effects, provided in an embodiment of this disclosure, is shown.

[0023] Figure 3 A Poincaré cross-sectional view of an arc-edged octagonal microcavity provided according to an embodiment of the present disclosure is shown schematically.

[0024] Figure 4 The diagram schematically illustrates the mode field distribution of a hybrid quadrilateral resonant mode of an arc-edged octagonal microcavity with a side length of 8 μm, a deformation of 0.2 μm, and a waveguide width of 2 μm, simulated using the finite element method according to an embodiment of the present disclosure.

[0025] Figure 5 The diagram schematically illustrates the variation of the quality factor of a mode in an arc-edged octagonal microcavity with a side length of 8 μm, a deformation of 0.2 μm, and a waveguide width of 2 μm, simulated using the finite element method according to an embodiment of the present disclosure, as a function of wavelength.

[0026] Figure 6 The diagram schematically illustrates the mode field distribution of a quadrilateral resonant mode after decoupling from an arc-edged octagonal microcavity with a side length of 8 μm, a deformation of 0.2 μm, a waveguide width of 2 μm, and a quadrilateral annular injection window width of 3.5 μm, as simulated using the finite element method according to an embodiment of the present disclosure.

[0027] Figure 7 The diagram schematically illustrates the power and voltage-current curves of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to an embodiment of the present disclosure at a TEC temperature of 293 K.

[0028] Figure 8A The illustration shows the spectrum of the semiconductor microcavity laser that spontaneously generates nonlinear effects according to an embodiment of the present disclosure, with the injection current continuously varying from 15 mA to 50 mA in 1 mA intervals.

[0029] Figure 8B The schematic diagram illustrates detailed spectra of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to embodiments of the present disclosure when the injection current is 16 mA, 27 mA, and 28 mA.

[0030] Figure 9A The illustration schematically shows the spectrum of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to an embodiment of the present disclosure, with the injection current continuously varying from 28 mA to 39 mA in 0.1 mA intervals.

[0031] Figure 9B Detailed spectra of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to embodiments of the present disclosure are illustrated for injection currents of 28.2 mA, 30.2 mA, 31.1 mA, 32 mA, 37.2 mA, and 38.3 mA. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0033] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0034] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0035] In the description of this disclosure, it should be understood that the terms "longitudinal", "length", "circumferential", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the subsystem or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.

[0036] Throughout the accompanying drawings, identical elements are represented by the same or similar reference numerals. Conventional structures or constructions have been omitted where they may cause confusion in understanding this disclosure. Furthermore, the shapes, dimensions, and positional relationships of the components in the drawings do not reflect actual size, scale, or actual positional relationships. Additionally, any reference numerals placed between parentheses in the claims should not be construed as limiting the claims.

[0037] Similarly, to simplify this disclosure and aid in understanding one or more of the various aspects of the disclosure, in the above description of exemplary embodiments of the present disclosure, various features of the present disclosure are sometimes grouped together in a single embodiment, figure, or description thereof. The use of terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refers to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present disclosure. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In realizing the concept of this disclosure, the applicant discovered that in a hexagonal microcavity with mixed triangular modes, the decoupled triangular modes can be selectively excited by setting a rotating parity-time symmetric region. By selectively electrically pumping a quadrupole deformable microcavity laser, both low threshold and directional lasing of the mixed triangular modes can be achieved simultaneously. Furthermore, for a quadrupole deformable microcavity with double triangular orbital modes, numerical simulations have demonstrated that spatially selective pumping along periodic orbits facilitates control of the laser mode under the nonlinear interaction between the optical field and the gain medium. Therefore, mixed modes in microcavities have the potential to achieve multiple functions and hold significant research value. To avoid external disturbances and precisely control the generation of nonlinear effects, further research is needed on the structure of semiconductor lasers and the corresponding implementation mechanisms to achieve spontaneous generation of nonlinear dynamic effects. Based on this, embodiments of this disclosure provide a semiconductor microcavity laser that spontaneously generates nonlinear effects.

[0040] Figure 1 A schematic three-dimensional structural diagram of a semiconductor microcavity laser that spontaneously generates nonlinear effects, provided in an embodiment of the present disclosure, is shown. Figure 2 A schematic diagram of a semiconductor microcavity laser that spontaneously generates nonlinear effects, provided in an embodiment of this disclosure, is shown.

[0041] like Figure 1 and Figure 2 As shown, the semiconductor microcavity laser that spontaneously generates nonlinear effects may include: an octagonal microcavity with arc edges 1, a quadrilateral ring electrode 2, and a waveguide 3.

[0042] The arc-edged octagonal microcavity 1 is used as a resonant cavity and is configured to generate a hybrid quadrilateral resonant mode through total internal reflection of light from the second-nearest side.

[0043] The quadrilateral ring electrode 2 is formed on the arc-edged octagonal microcavity 1 to decouple the hybrid quadrilateral resonant mode into a first quadrilateral resonant mode and a second quadrilateral resonant mode, so that the first quadrilateral resonant mode and the second quadrilateral resonant mode interact to produce nonlinear effects.

[0044] Waveguide 3 is used to receive the nonlinear effects generated by the interaction of two decoupled modes in the arc-edge octagonal microcavity 1 and output an optical signal.

[0045] In this embodiment, the straight side length corresponding to the arc-edge octagonal microcavity 1 can be, for example, 8 μm, the deformation (δ) represents the distance from the vertex of the arc edge to the straight side, and can be 0.2 μm, and the waveguide width can be 2 μm. The arc-edge octagonal microcavity only requires one photolithography step and does not require secondary epitaxy, making the fabrication process simple and saving production costs.

[0046] In this embodiment of the disclosure, the first track corresponding to the first quadrilateral resonant mode and the second track corresponding to the second quadrilateral resonant mode are independent of each other, which provides physical conditions for the decoupling of the hybrid resonant modes.

[0047] Furthermore, the quadrilateral ring electrode 2 has the same shape as one of the first and second orbitals, which helps to achieve sufficient decoupling of the hybrid resonant modes. For example, the width of the quadrilateral ring electrode 2 can be 3.5 μm.

[0048] In this embodiment of the present disclosure, the quadrilateral ring electrode 2 directly excites one of the first quadrilateral resonant modes and the second quadrilateral resonant modes through carrier injection. Since the field distributions of the first quadrilateral resonant mode and the second quadrilateral resonant mode overlap to a certain extent in space, and the carriers injected through the electrode diffuse laterally, under the influence of the overlap of the spatial optical field distribution and the lateral diffusion of the carriers, the first quadrilateral resonant mode and the second quadrilateral resonant mode lasing and interacting to produce nonlinear effects.

[0049] Furthermore, the frequency interval between the first quadrilateral resonant mode and the second quadrilateral resonant mode can be adjusted by regulating the charge carriers in the injected ring electrode 2. The frequency interval between the first and second quadrilateral resonant modes is 10 GHz to 14 GHz.

[0050] In this embodiment, waveguide 3 includes a first end face and a second end face. The first end face is directly connected to one vertex of the arc-edged octagonal microcavity 1, and the second end face is a cleavage surface 4. Since the mode field distribution is stronger at the midpoints of each side of the arc-edged octagonal microcavity and weaker at the corners, directly connecting the waveguide 3 to the vertex of the arc-edged octagonal microcavity 1 can both preserve the mode field distribution and ensure the mode's quality factor, while also achieving directional output. For example, waveguide 3 can be a strip waveguide for better directional transmission.

[0051] Furthermore, the arc-edge octagonal microcavity 1 and the waveguide 3 are formed on the same epitaxial wafer 5. The substrate of the epitaxial wafer is InP, and the active layer is an AlGaInAs multi-quantum-well structure. The arc-edge octagonal microcavity 1 is surrounded by divinylsiloxane dibenzocyclobutene 6 (BCB). BCB is used to confine the spatial optical field formed by the arc-edge octagonal microcavity 1, which can effectively reduce the leakage current of the device.

[0052] To more clearly illustrate the advantages of the semiconductor microcavity laser provided in the embodiments of this disclosure, some data are listed below for explanation.

[0053] Figure 3 A Poincaré cross-sectional view of an arc-edged octagonal microcavity provided according to an embodiment of the present disclosure is shown schematically.

[0054] like Figure 3 As shown, where χ is the angle of incidence of the light ray, and S represents the distance along the boundary in a clockwise direction. max The perimeter of the octagon with curved edges is represented. The refractive index of the octagonal microcavity 1 is 3.2, and the refractive index of BCB is 1.54. The solid line, represented by sinχ = 3.2 / 1.54, indicates the critical condition for total internal reflection in the TE mode. Only light rays below the solid line can escape from the resonator, and 200 random light rays are traced above the solid line. Once they enter the leakage region, the light rays are ignored. As shown in the Poincaré section diagram, the stable islands represented by squares and circles represent two quadrilateral resonant mode orbitals, indicating that the hybrid quadrilateral orbital mode is formed by the degenerate mode coupling of two independent orbitals, both located above the critical line for total internal reflection.

[0055] Figure 4 The diagram schematically illustrates the mode field distribution of a hybrid quadrilateral resonant mode of an arc-edged octagonal microcavity with a side length of 8 μm, a deformation of 0.2 μm, and a waveguide width of 2 μm, simulated using the finite element method according to an embodiment of the present disclosure.

[0056] like Figure 4 As shown, the hybrid quadrilateral resonant mode is formed by the coupling of two quadrilateral resonant modes. The quadrilateral orbit is formed by total internal reflection of light along the second-nearest side, and is marked with a dashed line. The field distributions of the two quadrilateral resonant modes overlap to some extent in space, but they are independent modes, which provides the physical conditions for the decoupling of the hybrid mode.

[0057] Figure 5 The diagram illustrates the variation of the quality factor of a mode in an arc-edged octagonal microcavity with a side length of 8 μm, a deformation of 0.2 μm, and a waveguide width of 2 μm, simulated using the finite element method according to an embodiment of the present disclosure, as a function of different wavelengths.

[0058] like Figure 5 As shown, there are three sets of longitudinal modes in the wavelength range of 1530 nm to 1570 nm. The longitudinal mode spacing corresponding to the mixed mode at wavelengths of 1538.9 nm and 1552.3 nm is 13.4 nm. Since each quadrilateral resonant mode is doubly degenerate, the pairwise coupling hybridization forms a quadruple degenerate mixed resonant mode, which is represented by a dashed box in the figure. The quality factor of the mixed quadrilateral resonant mode at wavelength of 1552.3 nm is 2.45 × 10⁻⁶. 4 2.35×10 4 7.61×10 3 and 6.85×10 3 Therefore, the hybrid quadrilateral resonant mode is a high-quality factor resonant mode with low scattering loss, which is beneficial for maintaining the high-quality factor of the decoupled mode and realizing low-threshold lasing.

[0059] Figure 6 The diagram schematically illustrates the mode field distribution of a quadrilateral resonant mode after decoupling from an arc-edged octagonal microcavity with a side length of 8 μm, a deformation of 0.2 μm, a waveguide width of 2 μm, and a quadrilateral annular injection window width of 3.5 μm, as simulated using the finite element method according to an embodiment of the present disclosure.

[0060] like Figure 6 As shown, by designing a quadrilateral-ring injection window with a width of w, its region closely resembles the field distribution of one of the modes in the mixed quadrilateral resonant modes. This is experimentally advantageous for separating the two quadrilateral resonant modes. We set the real part of the refractive index of the injection window to 3.2 + 0.003. Simulations show that the two decoupled quadrilateral resonant modes follow different trajectories, and the positions of their reflection points are... Figure 3 The positions of the stable islands in the Poincaré section diagram shown match, which further proves the independence of the two quadrilateral resonant modes and provides a physical basis for experimental decoupling.

[0061] Figure 7 The diagram schematically illustrates the power and voltage-current curves of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to an embodiment of the present disclosure at a TEC temperature of 293 K.

[0062] like Figure 7 As shown, the horizontal axis represents the injection current, and the vertical axis represents the total output power collected using multimode fiber. An octagonal microcavity laser with an 8μm side length, a deformation of 0.2μm, a waveguide width of 2μm, and an injection window width of 3.5μm has a threshold current of 3mA and a corresponding threshold current density of 0.97kA / cm². 2 Therefore, this laser achieves low threshold current density lasing. The series resistance, obtained by fitting the voltage-current curve at an injection current of 30 mA, is 22 ohms. The maximum output power is 89 μW at an injection current of 38 mA.

[0063] Figure 8A The illustration shows the spectrum of the semiconductor microcavity laser that spontaneously generates nonlinear effects according to an embodiment of the present disclosure, with the injection current continuously varying from 15 mA to 50 mA in 1 mA intervals.

[0064] like Figure 8A As shown, with the increase of the injection current, when the injection current is 28mA, the lasing mode exhibits mode hopping, with an interval of one longitudinal mode interval of 13.5nm, which is consistent with the simulation results. It can be seen that as the injection current increases from 28mA to 31mA, the main laser mode gradually shifts from 1559nm to 1572nm.

[0065] Figure 8B The schematic diagram illustrates detailed spectra of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to embodiments of the present disclosure when the injection current is 16 mA, 27 mA, and 28 mA.

[0066] like Figure 8B As shown, when the injection current increases from 16 mA to 27 mA, the semiconductor microcavity laser exhibits dual-mode lasing, with the two modes being decoupled quadrilateral modes. Since the refractive index of the semiconductor material is affected by carrier concentration and temperature, a non-uniform refractive index distribution is formed under non-uniform injection. The injection current density is higher in the injection window region, resulting in a higher carrier concentration and temperature in this region, thus forming a non-uniform carrier and temperature distribution. Therefore, this provides the conditions for the decoupling of the mixed quadrilateral modes. Simultaneously, due to the lateral diffusion of carriers, both quadrilateral modes can satisfy the threshold condition to achieve lasing. At an injection current of 16 mA, the wavelengths of the two lasing modes are 1556.95 nm and 1557.08 nm, respectively, with small side slits on both sides of the two main modes, corresponding to a four-wave mixing phenomenon. Due to thermal effects, at 27 mA, the main lasing peaks redshift to 1559.50 and 1559.63 nm. There are two sets of longitudinal modes at an injection current of 28mA. The quadrilateral modes of the decoupled different tracks are labeled as Ma and Mb, respectively. Ma preferentially jumps to the longitudinal mode near 1573nm, while Mb does not fully jump to the mode until 31mA.

[0067] Figure 9A The illustration schematically shows the spectrum of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to an embodiment of the present disclosure, with the injection current continuously varying from 28 mA to 39 mA in 0.1 mA intervals. Figure 9B Detailed spectra of a semiconductor microcavity laser that spontaneously generates nonlinear effects according to embodiments of the present disclosure are illustrated for injection currents of 28.2 mA, 30.2 mA, 31.1 mA, 32 mA, 37.2 mA, and 38.3 mA.

[0068] like Figure 9A and Figure 9BAs shown, with increasing injection current, when the current increases from 28 mA to 30.1 mA, the frequency spacing between the two-mode lasing Ma and Mb decreases from 14.25 GHz (0.114 nm) to 10 GHz (0.08 nm) because the redshift rate of Ma (0.26 nm / mA) is greater than that of Mb (0.23 nm / mA). This indicates that the wavelength spacing of the modes can be tuned by the injection current. Since the two modes with small frequency differences are easily locked through nonlinear interactions between the active medium, mode locking occurs between 30.2 mA and 31 mA. The wavelength redshift trajectory of the single mode is consistent with that of Ma, indicating that the mode is locked at Ma. Due to the complete mode jump of Mb from 1560 nm to 1573 nm, the spectrum exhibits a dual-mode lasing pattern with a small frequency interval of only 10 GHz. When the injection current is 31.1 mA, the transition from single-mode to dual-mode lasing occurs, with the wavelengths of lasing modes Ma and Mb at 1573.07 nm and 1573.15 nm, respectively. With further increases in the injection current, stronger nonlinear effects occur. When the injection current increases from 31.2 mA to 37.2 mA, a significant broadening of the lasing spectrum is observed, corresponding to a chaotic state. This is due to the spectral broadening caused by strong interactions between decoupled modes. At an injection current of 37.2 mA, four main peaks with intensity differences less than 3 dB are observed, with the wavelength interval between adjacent modes being half that of the two main modes Ma and Mb, corresponding to a double-period oscillation state. As the current increases from 37.2 mA to 38.3 mA, the laser state reverts to a dual-mode laser state. Therefore, this semiconductor microcavity laser can achieve spontaneously generated nonlinear dynamic effects, including mode locking, four-wave mixing, double-period oscillation, and chaos.

[0069] In summary, the semiconductor microcavity laser that spontaneously generates nonlinear effects provided in this disclosure uses an arc-edged octagonal microcavity structure as its resonant cavity. Since a hybrid quadrilateral resonant mode, formed by the coupling of two quadrilateral resonant modes, naturally exists within the arc-edged octagonal microcavity, and decoupling of the hybrid mode is achieved by designing a ring electrode along the trajectory of one of the resonant modes, nonlinear effects can be spontaneously generated based on the interaction between the two decoupled modes of the independent laser, without the need for complex experimental modulation. The two resonant modes of the decoupled semiconductor microcavity laser can simultaneously lasing and interact due to the diffusion of transverse current. The frequency interval between the two modes can be adjusted by changing the injected carriers, allowing for flexible control of the generation of different types of nonlinear effects. The first end face is directly connected to one vertex of the arc-edged octagonal microcavity. Since the mode field distribution is stronger at the midpoints of each side of the arc-edged octagonal microcavity and weaker at the corners, directly connecting a waveguide at the vertex of the arc-edged octagonal microcavity can both preserve the mode field distribution and ensure the mode's quality factor, while also achieving directional output. The waveguide and cavity are grown on the same epitaxial wafer with InP as the substrate and an AlGaInAs multi-quantum-well structure as the active layer. The cavity is surrounded by divinylsiloxane bisbenzocyclobutene, which effectively reduces device leakage current. Furthermore, this semiconductor microcavity laser features simple fabrication, low cost, high yield and reliability, and is easy to integrate on-chip. In summary, this semiconductor microcavity laser, which spontaneously generates nonlinear effects, avoids external disturbances, exhibits flexibility and controllability, and paves the way for future applications of nonlinear dynamics.

[0070] The specific embodiments described above further illustrate the purpose, technical solutions, and beneficial effects of this disclosure. It should be understood that the above descriptions are merely specific embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A semiconductor microcavity laser that spontaneously generates nonlinear effects, characterized in that, include: An octagonal microcavity with curved edges (1) is configured to generate a hybrid quadrilateral resonant mode by total internal reflection of light from the second-nearest side; A quadrilateral ring electrode (2) is formed on the arc-edged octagonal microcavity (1) to decouple the hybrid quadrilateral resonant mode into a first quadrilateral resonant mode and a second quadrilateral resonant mode, so that the first quadrilateral resonant mode and the second quadrilateral resonant mode interact to produce a nonlinear effect. The quadrilateral ring electrode (2) directly excites one of the first quadrilateral resonant modes and the second quadrilateral resonant mode through carrier injection. Under the influence of the overlapping spatial optical field distributions of the first quadrilateral resonant mode and the lateral diffusion of the carriers, the first quadrilateral resonant mode and the second quadrilateral resonant mode lasing and interacting to produce nonlinear effects. The frequency interval between the first quadrilateral resonant mode and the second quadrilateral resonant mode is adjusted by adjusting the carriers injected into the quadrilateral ring electrode (2). The frequency interval between the first quadrilateral resonant mode and the second quadrilateral resonant mode is 10 GHz - 14 GHz. The two decoupled quadrilateral resonant modes propagate along different tracks, wherein the first track corresponding to the first quadrilateral resonant mode and the second track corresponding to the second quadrilateral resonant mode are independent of each other. When the current increases from 28 mA to 30.1 mA, the redshift rate of the first quadrilateral resonant mode is 0.26 nm / mA, the redshift of the second quadrilateral resonant mode is 0.23 nm / mA; the shape of the quadrilateral ring electrode (2) is the same as the shape of one of the first and second orbitals; Waveguide (3) is used to receive the nonlinear effect generated by the arc-edge octagonal microcavity (1) to realize the output of optical signal.

2. The semiconductor microcavity laser according to claim 1, characterized in that, The waveguide (3) includes a first end face and a second end face. The first end face is directly connected to one of the vertices of the arc-edged octagonal microcavity (1), and the second end face is a cleavage surface.

3. The semiconductor microcavity laser according to claim 2, characterized in that, The waveguide (3) is a strip waveguide.

4. The semiconductor microcavity laser according to claim 1, characterized in that, The arc-edge octagonal microcavity (1) and the waveguide (3) are formed on the same epitaxial wafer, the substrate of which is InP and the active layer is an AlGalnAs multi-quantum-well structure.

5. The semiconductor microcavity laser according to claim 4, characterized in that, The arc-edged octagonal microcavity (1) is surrounded by divinylsiloxane bisbenzocyclobutene, which is used to confine the spatial light field formed by the arc-edged octagonal microcavity (1).

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