Electronically pumped complex-coupled distributed feedback laser cavity and laser

Abstract

The application discloses an electrically pumped complex-coupled distributed feedback laser resonant cavity and a laser, and the laser resonant cavity comprises a gain material layer; a first doped cladding buffer layer is arranged above the gain material layer, the first doped cladding buffer layer is formed into a waveguide ridge with a middle protrusion through etching, a surface layer of a remaining area on both sides of the waveguide ridge is provided with a dielectric isolation layer, and a top surface of the dielectric isolation layer is a plane; a second doped cladding buffer layer is arranged below the gain material layer; a first Bragg array is arranged on a surface layer of both sidewalls or both sides of the remaining area of the waveguide ridge; a second Bragg array is arranged on the dielectric isolation layer; a first electrode is arranged on a top surface of the waveguide ridge; and a second electrode is arranged on a bottom surface of the second doped cladding buffer layer. When the current is injected through the N-type metal electrode and the P-type metal electrode and the current density of the laser reaches above a threshold value, the laser can realize stable single-frequency laser output and has strong resistance to external echoes.

Description

Technical Field

[0001] This invention relates to the field of semiconductor laser device technology, and in particular to an electrically pumped complex-coupled distributed feedback laser resonator and laser. Background Technology

[0002] Single-frequency lasers, with their high stability, narrow linewidth, and dynamic tunability, have become indispensable core light sources in cutting-edge fields such as precision spectroscopy, high-speed long-distance optical communication, coherent detection, and quantum information processing. Their research is not only crucial for in-depth exploration of laser physics but also of great significance for breakthroughs in the performance of next-generation optoelectronic devices. Traditional lasers suffer from insufficient spectral purity due to multimode operation, making it difficult to meet the demands of high-precision applications. Distributed feedback lasers (DFBs), through periodic modulation of Bragg gratings, achieve effective mode selection and have become the mainstream solution for current single-frequency lasers. However, this technology still faces significant bottlenecks: the resonant cavity of traditional dielectric DFB lasers suffers from mode degeneracy, leading to severe single-mode stability issues due to end-face reflection; while phase-shifted DFB laser resonant cavities suppress side-mode oscillations by introducing a λ / 4 phase shift, the non-uniform carrier distribution causes severe longitudinal spatial hole burning, limiting output power and linewidth performance. Distributed Bragg reflectors (DBRs) employ a separate design for the grating and active region, which improves wavelength tuning flexibility. However, the reduced grating coupling efficiency and complex secondary epitaxial processes limit their performance and cost advantages. Loss-coupled DFB lasers based on metal gratings achieve excellent single-frequency selectivity by introducing a mode-correlation loss mechanism, but the high threshold voltage and thermal effects caused by metal absorption severely restrict their practical application. Therefore, existing single-frequency lasers suffer from poor performance in practical applications. Summary of the Invention

[0003] This invention provides an electrically pumped complex-coupled distributed feedback laser resonator and laser, aiming to solve the problem of poor performance of single-frequency lasers in practical applications in existing technologies.

[0004] In a first aspect, embodiments of this application provide an electrically pumped complex-coupled distributed feedback laser resonator, characterized in that the laser resonator includes a gain material layer;

[0005] The first doped cladding buffer layer is disposed above the gain material layer. The first doped cladding buffer layer is etched to form a waveguide ridge with a raised center. The surface of the remaining etched areas on both sides of the waveguide ridge is provided with a dielectric isolation layer. The top surface of the dielectric isolation layer is a plane.

[0006] The second doped coating buffer layer is disposed below the gain material layer;

[0007] The waveguide ridge has a first Bragg array on the surface of the two side walls or the remaining etched areas on both sides of the waveguide ridge; the first Bragg array is a non-destructive Bragg array.

[0008] A second Bragg array is provided on the dielectric isolation layer; the second Bragg array is a loss / gain Bragg array.

[0009] The top surface of the waveguide ridge is provided with a first electrode; the bottom surface of the second doped cladding buffer layer is provided with a second electrode.

[0010] The dielectric isolation layer isolates the first doped coating buffer layer from the second Bragg array;

[0011] The first Bragg array and the second Bragg array are provided with a preset displacement of up to 2π.

[0012] The electrically pumped complex-coupled distributed feedback laser resonator, wherein the refractive index of the gain material layer is greater than that of the first doped cladding buffer layer and the second doped cladding buffer layer, and the gain material layer is prepared from a material that provides interband recombination or subband transition.

[0013] The electrically pumped complex-coupled distributed feedback laser resonator, wherein the distance between the bottom of the waveguide ridge and the gain material layer is no greater than 1 / 20 of λ, where λ is the operating wavelength of the laser master mode.

[0014] The electrically pumped complex-coupled distributed feedback laser resonator, wherein the periods of the first Bragg array and the second Bragg array are both d, where d = m*λ / (2*n) eff ); m is the diffraction series of the Bragg array, n eff is the effective refractive index of the laser resonant cavity.

[0015] The electrically pumped complex-coupled distributed feedback laser resonator, wherein the first Bragg array is disposed on both sides of the waveguide ridge, and the first doped cladding buffer layer is etched from top to bottom based on the Bragg array mask to obtain a waveguide ridge with Bragg structure on both sides.

[0016] Alternatively, the first Bragg array is disposed on the surface layer of the remaining etched area on both sides of the waveguide ridge, and a planar Bragg structure is fabricated with the centerline of the waveguide ridge as the axis of symmetry as the first Bragg array.

[0017] The unit structure of the first Bragg array is composed of a first strip, the length of the minor axis of the first strip is less than the Bragg period d, and the length of the first strip along the major axis is not less than 5λ.

[0018] In the electrically pumped complex-coupled distributed feedback laser resonator, the thickness of the dielectric isolation layer is no greater than 1 / 50 of λ; the refractive index of the dielectric isolation layer is less than the refractive indices of the first doped cladding buffer layer and the second doped cladding buffer layer.

[0019] The electrically pumped complex-coupled distributed feedback laser resonator, wherein the second Bragg array is disposed on the dielectric isolation layers on both sides of the waveguide ridge with the centerline of the waveguide ridge as the axis of symmetry; the unit structure of the second Bragg array is composed of parallel second strips; the short axis length of the second strip is less than the Bragg period d, and the length of the second strip along the long axis is not less than 5λ.

[0020] The electrically pumped complex-coupled distributed feedback laser resonator wherein the unit structure shape of the first Bragg array and the second Bragg array is any one of cuboid, sawtooth, sine, or cosine shapes, or a combination of multiple shapes.

[0021] The electrically pumped complex-coupled distributed feedback laser resonator, wherein the second electrode is an N-type metal electrode, the second doped cladding buffer layer is an N-type doped cladding buffer layer, the first doped cladding buffer layer is a P-type doped cladding buffer layer, and the first electrode is a P-type metal electrode; or, the second electrode is a P-type metal electrode, the second doped cladding buffer layer is a P-type doped cladding buffer layer, the first doped cladding buffer layer is an N-type doped cladding buffer layer, and the first electrode is an N-type metal electrode.

[0022] Secondly, embodiments of the present invention also disclose a laser, wherein the laser includes the electrically pumped complex-coupled distributed feedback laser resonator described in the above embodiments.

[0023] This invention provides an electrically pumped complex-coupled distributed feedback laser resonator and laser. The laser resonator includes a gain material layer; a first doped cladding buffer layer is disposed above the gain material layer, and the first doped cladding buffer layer is etched to form a waveguide ridge with a central ridge. The surface of the remaining etched areas on both sides of the waveguide ridge is provided with a dielectric isolation layer, and the top surface of the dielectric isolation layer is planar; a second doped cladding buffer layer is disposed below the gain material layer; a first Bragg array is provided on the side walls of the waveguide ridge or on the surface of the remaining etched areas on both sides of the waveguide ridge; a second Bragg array is provided on the dielectric isolation layer; a first electrode is provided on the top surface of the waveguide ridge; and a second electrode is provided on the bottom surface of the second doped cladding buffer layer. The aforementioned laser resonant cavity, by adjusting the amplitude and phase difference of the Bragg array, can precisely control the complex coupling coefficients between modes within the resonant cavity of a distributed feedback laser composed of dual Bragg arrays, thereby obtaining a single-frequency laser with low loss, high transmission, and narrow linewidth characteristics. When current is injected through N-type and P-type metal electrodes and the current density of the laser reaches a threshold or higher, the laser can achieve stable single-frequency laser output and has strong resistance to external echoes. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 An overall structural diagram of a laser resonator of a first configuration provided in an embodiment of the present invention;

[0026] Figure 2 A top view of the laser resonator of the first configuration provided in this embodiment of the invention;

[0027] Figure 3 A side view of the laser resonator of the first configuration provided in this embodiment of the invention;

[0028] Figure 4 Another side view of the laser resonator cavity of the first configuration provided in the embodiments of the present invention;

[0029] Figure 5 This is an overall structural diagram of a laser resonator with a second configuration provided in an embodiment of the present invention;

[0030] Figure 6 A top view of the laser resonator of the second configuration provided in this embodiment of the invention;

[0031] Figure 7 A side view of the laser resonator of the second configuration provided in this embodiment of the invention;

[0032] Figure 8 Another side view of the laser resonator cavity of the second configuration provided in the embodiment of the present invention;

[0033] Figure 9 This is an overall structural diagram of a laser resonator with a third configuration provided in an embodiment of the present invention;

[0034] Figure 10 A top view of the laser resonator of the third configuration provided in this embodiment of the invention;

[0035] Figure 11 A side view of the laser resonator with a third configuration provided in this embodiment of the invention;

[0036] Figure 12 This is a side view of the laser resonator cavity of the third configuration provided in an embodiment of the present invention.

[0037] Figure label:

[0038] Example 1: 101, P-type metal electrode; 102, P-type doped coating buffer layer; 102A, vertical groove; 102B, first strip; 102C, etched remaining area; 103, dielectric isolation layer; 104A, second Bragg array A; 104B, second Bragg array B; 105, gain material layer; 106, N-type doped coating buffer layer; 107, N-type metal electrode; 108A, first gap; 108B, second gap.

[0039] Example 2: 201, P-type metal electrode; 202, P-type doped cladding buffer layer; 202A, waveguide ridge; 202B, first Bragg array; 203, dielectric isolation layer; 203A, dielectric isolation layer embedding portion; 204A, second Bragg array A; 204B, second Bragg array B; 205, gain material layer; 206, N-type doped cladding buffer layer; 207, N-type metal electrode; 208A, first gap; 208B, second gap.

[0040] Example 3: 301, P-type metal electrode; 302, P-type doped cladding buffer layer; 302A, waveguide ridge; 302B, first Bragg array; 303, gain material layer; 303A, gain material layer protrusion; 304, dielectric isolation layer; 304A, dielectric isolation layer embedding portion; 305A, second Bragg array A; 305B, second Bragg array B; 306, N-type doped cladding buffer layer; 307, N-type metal electrode; 308A, first gap; 308B, second gap. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0043] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0044] This invention provides an electrically pumped complex-coupled distributed feedback laser resonator, aiming to overcome the technical defects of existing lasers and achieve laser output with low threshold voltage, high power, and excellent single-frequency stability. The laser resonator in this embodiment can be assembled within a complex-coupled distributed feedback laser resonator to obtain a distributed feedback laser and perform laser output.

[0045] The laser resonator disclosed in this invention operates on a core mechanism based on the mode selection mechanism of a dual Bragg array; for example... Figure 1 , Figure 5 and Figure 9 As shown, the first and second Bragg arrays combine to form a dual Bragg array. The first Bragg array is a lossless Bragg array, and the second Bragg array is a loss / gain Bragg array, consisting of second Bragg array A and second Bragg array B. The lossless Bragg array is configured to periodically control the real part of the refractive index within the laser resonant cavity; the loss / gain Bragg array is configured to periodically control the imaginary part of the refractive index within the laser resonant cavity. A preset displacement is provided between the lossless Bragg array and the loss / gain Bragg array to provide a specific phase difference.

[0046] The gain material layer of this invention is used for light generation, waveguided transmission, and amplification. The gain band design of the gain material layer is independent of the mode modulation mechanism of this invention, and the working mechanism of this invention is not limited to the laser operating band. Therefore, the laser gain medium of this invention can support light emission mechanisms including, but not limited to, direct bandgap recombination, indirect bandgap recombination, and inter-subband transitions. The gain material layer is composed of a material that can provide inter-band recombination or inter-subband transitions, and the refractive index of the gain material layer is greater than that of the first and second cladding layers, thereby providing an optical waveguide function.

[0047] The first doped coating buffer layer is disposed above the gain material layer, and the second doped coating buffer layer is disposed below the gain material layer.

[0048] The waveguide ridge can be etched in the first doped cladding buffer layer or the first doped cladding buffer layer, and the distance between the bottom of the waveguide ridge and the gain material layer is within 1 / 20 of the working wavelength.

[0049] The first Bragg array can be located in the waveguide ridge, that is, by using a Bragg array mask to etch the first doped cladding buffer layer from top to bottom to form a waveguide ridge with a Bragg structure; or, the waveguide ridge does not contain the first Bragg array, and the first Bragg array is fabricated by etching the remaining first doped cladding buffer layer on both sides of the waveguide ridge with the centerline of the waveguide ridge as the axis of symmetry; the unit structure of the first Bragg array is composed of a first strip, the length of the minor axis of the first strip is less than the Bragg period d, and the length of the first strip along the major axis is not less than 5λ.

[0050] The dielectric isolation layer is symmetrically arranged on both sides of the waveguide ridge with the centerline of the waveguide ridge as the axis of symmetry. If the first Bragg array is in the waveguide ridge, the dielectric isolation layer is uniformly distributed on both sides of the waveguide ridge above the etched remaining first doped cladding buffer layer, with a thickness not exceeding 1 / 50 of the working wavelength. If the first Bragg array is distributed on both sides of the waveguide ridge, the dielectric isolation layer, while filling the first Bragg array, overflows the upper part of the etched first doped cladding buffer layer by a thickness not exceeding 1 / 50 of the working wavelength. The refractive index of the dielectric isolation layer is less than the refractive index of the first doped cladding buffer layer and the second doped cladding buffer layer.

[0051] The second Bragg array does not contact the waveguide ridge. It is symmetrically positioned on both sides of the waveguide ridge, with the centerline of the ridge as the axis of symmetry. The Bragg period direction of this array is parallel to the waveguide ridge direction, and the length of the array on any one side in the lateral direction is not less than 5 times the operating wavelength. The second Bragg array is positioned on both sides of the waveguide ridge, with the centerline of the ridge as the axis of symmetry. The unit structure of the second Bragg array consists of parallel second strips. The minor axis length of the second strip is less than the Bragg period d, and the length of the second strip along its major axis is not less than 5λ.

[0052] The period of each Bragg array (corresponding to the first and second Bragg arrays) is d, where d = m * λ / (2 * n) eff ); m is the diffraction order of the lossless Bragg array, n eff λ is the effective refractive index of the laser resonant cavity; λ is the operating wavelength of the laser master mode; and there is a preset phase displacement of less than 2π between the first Bragg array and the second Bragg array.

[0053] The unit structure shape of the first Bragg array and the second Bragg array is any one of cuboid, sawtooth, sine, cosine, or a combination of the above shapes.

[0054] The second electrode is an N-type metal electrode, the second doped coating buffer layer is an N-type doped coating buffer layer, the first doped coating buffer layer is a P-type doped coating buffer layer, and the first electrode is a P-type metal electrode; or, the second electrode is a P-type metal electrode, the second doped coating buffer layer is a P-type doped coating buffer layer, the first doped coating buffer layer is an N-type doped coating buffer layer, and the first electrode is an N-type metal electrode.

[0055] The composition structure of the gain material layer can be selected in several ways: (1) Direct bandgap double heterojunction structure, where the active layer is directly a group III-V semiconductor material layer, such as InGaAsP, which can be directly combined with a P-type doped cladding buffer layer and an N-type doped cladding buffer layer to form a double heterojunction structure for light generation and optical waveguide effects; (2) Direct bandgap quantum well structure, where the gain material waveguide layer of this structure is usually a sandwich structure consisting of an upper separated confined heterojunction (SCH) - multiple quantum wells (MQW) - a lower separated confined heterojunction (SCH). The structure consists of multiple repeating cascaded units, each of which includes multiple alternating stacked III-V semiconductor heterostructures. Its core feature is to use the quantum confinement effect to discretize the electronic energy levels in the quantum well, forming multiple sub-bands. Electrons are transported, transitioned, and release photons between the sub-bands. Furthermore, the gain is enhanced and laser emission is achieved through series connection between each period. (4) The structure consists of multiple repeating cascaded units, each of which includes alternating stacked narrow bandgap quantum wells and wide bandgap barrier layers. Its core feature is to use the transition of electrons between the conduction band and the valence band to generate photons. Each unit achieves the transfer and recycling of charge carriers through the charge injection layer, forming a series gain structure to achieve laser emission.

[0056] The materials used to fabricate laser resonators are applicable not only to material systems used in Group III-V semiconductor lasers, such as AlGaAs / GaAs, InGaAsP / InP, and InGaN / GaN; but also to material systems used in Group II-VI semiconductor lasers, such as ZnCdSe / ZnSe, BeMgSSe, and ZnMgSSe; and to material systems used in Group IV semiconductor lasers, such as Si-based and Ge-based lasers, as well as other material systems used in hybrid semiconductor lasers, such as InP-on-Si and GaAs-on-Si.

[0057] The gain band is designed according to the operating wavelength of the laser master mode. For example, if the operating wavelength is set to 1550nm, the gain band of the gain material layer needs to be set to cover the operating wavelength. After selecting the gain bandwidth, this invention performs mode selection and control within the gain band through the effective refractive index of the laser resonator and the dual Bragg array. Therefore, the above-mentioned gain band design and mode selection mechanism of this invention are independent of each other.

[0058] Example 1

[0059] The laser resonator in this embodiment corresponds to the first configuration. For example... Figure 1 As shown, the laser resonant cavity includes a gain material layer 105, a P-type doped cladding buffer layer 102 disposed above the gain material layer 105, and a waveguide ridge with a central ridge formed by etching in the P-type doped cladding buffer layer 102. A dielectric isolation layer 103 is disposed on the surface of the remaining etched regions 102C on both sides of the waveguide ridge, and the top surface of the dielectric isolation layer 103 is planar. A second doped cladding buffer layer is disposed below the gain material layer 105. A first Bragg array is disposed on both side walls of the waveguide ridge; the first Bragg array is a lossless Bragg array. A second Bragg array is disposed on the dielectric isolation layer 103; the second Bragg array is a lossless Bragg array. The waveguide ridge has a first electrode on its top surface and a second electrode on its bottom surface. A dielectric isolation layer 103 isolates the first doped buffer layer from the second Bragg array. Dielectric isolation layers 103 are provided on the etched remaining areas 102C on both sides of the waveguide ridge, with the top surface of each dielectric isolation layer 103 being planar. Second Bragg arrays A104A and B104B are respectively provided on the two dielectric isolation layers 103. Both second Bragg arrays A104A and B104B are loss / gain Bragg arrays.

[0060] In this embodiment of the application, a first Bragg array is respectively arranged on the two side walls facing the waveguide ridge, and its specific structure is as follows: Figure 1As shown. The two sidewalls of the waveguide ridge are etched inward to form the vertical grooves 102A, and multiple parallel first stripes 102B are formed between the vertical grooves 102A as the first Bragg array. The waveguide ridge can be etched from top to bottom in the P-doped semiconductor layer, and the size of the waveguide ridge can be matched to the active layer to achieve a lateral fundamental mode operating mode.

[0061] Taking the structure shown in Example 1 as an example, the P-type doped cladding buffer layer 102 typically includes a P-cladding layer and a P-contact layer with different doping concentrations; wherein the P-cladding layer contacts the gain material waveguide layer, and the P-contact layer is located between the P-side electrode and the P-cladding layer. The N-type doped semiconductor layer typically includes an N-cladding layer, an N-contact layer, and an N-substrate with different doping concentrations; wherein the N-cladding layer contacts the gain material waveguide layer, and the N-contact layer and the N-substrate are located near the N-side electrode and the N-cladding layer, and the N-substrate contacts the N-side electrode.

[0062] In this embodiment, the N-type metal electrode 107 and the N-type doped coating buffer layer 106 can be replaced with a P-type metal electrode and a P-type doped coating buffer layer; the P-type doped coating buffer layer 102 and the P-type metal electrode 101 can be replaced with an N-doped coating buffer layer and an N-type metal electrode respectively. Interchanging the polarities does not affect the function of the laser resonator in this application.

[0063] In a more specific embodiment, the unit structures of the second Bragg array A104A and the second Bragg array B104B are both composed of parallel second strips arranged together, with a second groove formed between the second strips; the major axis of the second strips is perpendicular to the central axis of the laser resonant cavity; the unit structure of the first Bragg array is composed of first strips 102B disposed on both sides of the waveguide ridge; the first strips 102B are arranged in parallel and their major axis is perpendicular to the central axis of the laser resonant cavity; a strip gap is formed between the first strips 102B. Specifically, the periods of the second Bragg array A104A, the second Bragg array B104B, and the first Bragg array are all equal; the period of the second Bragg array A104A and the second Bragg array B104B is the sum of the width of the second strip and the width of the second groove; the period of the first Bragg array is the sum of the width of the first strip 102B and the strip gap.

[0064] Specifically, the period of the first Bragg array is d = m * λ / (2 * n) eff ); m is the diffraction order of the first Bragg array, n effLet λ be the effective refractive index of the laser resonant cavity; λ be the operating wavelength of the laser's master mode, then the length of the resonant unit structure in this direction is less than the period d. The thickness of the dielectric isolation layer 103 is no greater than 1 / 50 of λ. Furthermore, the spacing between the second Bragg array A104A and the second Bragg array B104B and the gain material layer 105 is no greater than 1 / 10 of λ. Specifically, the length of the second strip in the second Bragg array A104A and the second Bragg array B104B along its major axis is no less than 5λ.

[0065] The gap between the second Bragg array A104A and the waveguide ridge is also known as the first gap 108A, and the gap between the second Bragg array B104B and the waveguide ridge is also known as the second gap 108B. H102C is the thickness of the remaining etched regions 102C on both sides of the waveguide ridge. The first gap 108A and the second gap 108B are set to prevent the gain / loss Bragg array from contacting the P-type doped cladding buffer layer 102, thus avoiding short circuits.

[0066] Dielectric isolation layers 103 are provided between the second Bragg array A104A and the first Bragg array on the same side, and between the second Bragg array B104B and the first Bragg array on the same side, to avoid short circuits between the P electrode and the loss / gain conductive array during current injection; the thickness of the dielectric isolation layer 103 is no greater than 1 / 50 of the operating wavelength λ.

[0067] In this embodiment, electron beam lithography (EBL) or ultraviolet lithography (UVL) can be used multiple times in conjunction with metal deposition processes. First, a P-type metal electrode 101 is fabricated. Then, a waveguide ridge containing a first Bragg array is etched from top to bottom into the P-type doped buffer layer 102. A first Bragg array is disposed on each side wall of the waveguide ridge. Ideally, the two first Bragg arrays are symmetrically distributed along the central axis of the waveguide ridge. Each first Bragg array includes a vertical groove 102A (short amplitude modulation portion) and a first strip 102B (long amplitude modulation portion). The difference in modulation amplitude of the first Bragg array is D102, which is also the height of the first strip 102B protruding outward. A P-type doped buffer layer 102 with a thickness not exceeding 1 / 20 of the working wavelength is retained at the bottom of the first Bragg array from the surface of the gain material layer 105. To prevent short circuits, a dielectric isolation layer 103 needs to be deposited first to isolate the second Bragg array 104 from the P-type doped buffer layer 102. The thickness of the dielectric isolation layer 103 is H103. In this embodiment of the invention, the value of H103 does not exceed 1 / 50 of the operating wavelength. Subsequently, a second Bragg array 104 (including a second Bragg array A104A and a second Bragg array B104B) is deposited on both sides of the bottom of the first Bragg array and on top of the dielectric isolation layer 103. The period of the second Bragg array 104 is P104 (the period of the second Bragg array A104A corresponds to P104A, and the period of the second Bragg array B104B corresponds to P104B), the width of the cell structure is W104 (the width of the second Bragg array A104A corresponds to W104A, and the width of the second Bragg array B104B corresponds to W104B), the lateral length of the cell structure is L104 (the lateral length of the second Bragg array A104A corresponds to L104A, and the lateral length of the second Bragg array B104B corresponds to L104B), and the height / thickness of the cell structure is H104 (the thickness of the second Bragg array A104A corresponds to H104A, and the thickness of the second Bragg array B104B corresponds to H104B). In principle, the second Bragg array A104A and the second Bragg array B104B have the same physical parameters, but in actual implementation, there may be some errors. The period P102 of the first Bragg array and the period P104 of the second Bragg array have the same value, and the phase difference between the two Bragg arrays is denoted as Φ102-104.

[0068] The real modulation amplitude of the first Bragg array is denoted as D102, and the imaginary modulation amplitude of the second Bragg array is denoted as H104. By adjusting the real modulation amplitude D102, the imaginary modulation amplitude H104, and the phase difference Φ102-104 between the two arrays, the complex coupling coefficients between the modes of the complex coupled distributed feedback (DFB) resonator composed of dual Bragg arrays can be precisely controlled, thereby effectively adjusting the optical field and modes within the resonator. Through the above adjustments, a single-frequency mode with low loss, high transmission, and narrow linewidth characteristics is finally selected. When current is injected into the laser through the P-type metal electrode 101 and the N-type metal electrode 107, and the current density of the laser reaches a state above the threshold, the laser can achieve a stable single-frequency laser output.

[0069] When the first and second Bragg arrays are in phase (i.e., the phase difference Φ10²-10⁴ is 0), the corresponding complex-coupled distributed feedback DFB resonator exhibits significant photonic bandgap characteristics. The loss characteristics of the side modes on either side of this bandgap differ significantly: one side mode has a lower loss value compared to the surrounding FP (Fabry-Perot Mode) modes, while the other side mode has a higher loss value. Based on this characteristic, the low-loss bandgap side mode can be selected as the operating mode to achieve narrowband single-frequency laser emission. Correspondingly, when the first and second Bragg arrays are out of phase (i.e., the phase difference Φ10²-10⁴ is π, where π is a radian value corresponding to an angle of 180°), the loss characteristics of the side modes on both sides of the bandgap exhibit an inverted distribution; the high-loss bandgap side mode in the in-phase state transforms into a low-loss mode, and the low-loss bandgap side mode in the in-phase state transforms into a high-loss mode.

[0070] When the phase difference Φ10²-10⁴ between the first Bragg array and the damaged second Bragg array is in a non-zero and non-π range (corresponding to radian ranges of (0,π) and (0,2π)), the laser can still maintain single-frequency laser output; however, the side-mode suppression ratio in this operating state shows a weakening trend compared to when the phase difference Φ10²-10⁴ is 0 or π. Furthermore, the resonant cavity of the complex-coupled laser in this phase range exhibits asymmetric reflection characteristics, especially when the phase difference Φ10²-10⁴ is π / 2 or 3π / 2, the asymmetric reflection phenomenon is maximized, and the asymmetric reflection directions corresponding to a phase difference Φ10²-10⁴ of π / 2 and 3π / 2 are opposite.

[0071] When the phase difference Φ102-104 between the first and second Bragg arrays is π / 2 or 3π / 2, the complex coupled distributed feedback DFB structure forms a parity-time (PT) symmetric potential field: when the real modulation amplitude D102 is greater than the imaginary modulation amplitude H104, the complex coupled distributed feedback DFB structure satisfies the PT symmetry condition and exhibits the same mode-merging characteristics as the pure real modulation DFB, and cannot achieve single-frequency laser output; when the real modulation amplitude D102 is less than the imaginary modulation amplitude H104, the complex coupled distributed feedback DFB structure experiences PT symmetry breaking, exhibits the same operating characteristics as the pure imaginary modulation DFB, forms a stable output at the Bragg wavelength position, and has excellent single-frequency operating performance.

[0072] Example 2

[0073] The laser resonator in this embodiment corresponds to the second configuration. For example... Figure 5 As shown, the laser resonant cavity includes a gain material layer 205, a P-type doped cladding buffer layer 202 disposed above the gain material layer 205, and a waveguide ridge 202A with a central ridge formed by etching the P-type doped cladding buffer layer 202. A dielectric isolation layer 203 is disposed on the surface of the remaining etched area of ​​the waveguide ridge 202A, and the top surface of the dielectric isolation layer 203 is planar. A second doped cladding buffer layer is disposed below the gain material layer 205. A first Bragg array 202B is disposed on the dielectric isolation layer 203 on the surface of the remaining etched area of ​​the waveguide ridge 202A. The first Bragg array 202B is a lossless Bragg array. A second Bragg array is disposed on the dielectric isolation layer 203. The waveguide ridge 202A has a first electrode on its top surface and a second electrode on its bottom surface. A dielectric isolation layer 203 isolates the first doped buffer layer from the second Bragg array. A dielectric isolation layer 203 is provided on the remaining etched area of ​​the waveguide ridge 202A, and the top surface of the dielectric isolation layer 203 is planar. A second Bragg array A204A and a second Bragg array B204B are respectively provided on the two dielectric isolation layers 203. Both the second Bragg array A204A and the second Bragg array B204B are loss / gain Bragg arrays.

[0074] In this embodiment, a first Bragg array 202B is respectively disposed on the remaining etched areas on both sides of the two waveguide ridges, as shown in the specific structure. Figure 5As shown. The top surfaces of the remaining etched areas on both sides of the waveguide ridge are etched inwards to form parallel grooves; multiple outwardly protruding and parallel first stripes are formed between the parallel grooves, serving as the first Bragg array 202B; the bottom surface of the dielectric isolation layer 203 is embedded in the parallel grooves, and the portion of the dielectric isolation layer 203 embedded in the parallel grooves is the dielectric isolation layer embedding portion 203A. The waveguide ridge 202A can be etched from top to bottom in the P-doped semiconductor layer, and the size of the waveguide ridge 202A can be matched with the active layer to achieve a lateral fundamental mode operating mode. Then, two remaining etched areas are formed on both sides of the waveguide ridge 202A. Further etching is performed on the surfaces of the remaining etched areas on both sides of the waveguide ridge to obtain the first Bragg array 202B.

[0075] In this embodiment, the N-type metal electrode 207 and the N-type doped coating buffer layer 206 can be replaced with the P-type metal electrode and the P-type doped coating buffer layer 202; the P-type doped coating buffer layer 202 and the P-type metal electrode 201 can be replaced with the N-doped coating buffer layer and the N-type metal electrode respectively. Interchanging the polarities does not affect the function of the laser resonator in this application.

[0076] In a more specific embodiment, the unit structures of the second Bragg array A204A and the second Bragg array B204B are both composed of parallel second strips arranged together, with a second groove formed between the second strips; the long axis of the second strips is perpendicular to the central axis of the laser resonator; the unit structure of the first Bragg array 202B is composed of first strips disposed on the dielectric isolation layer of the etched remaining area on both sides of the waveguide ridge; the first strips are arranged in parallel and the long axis of the first strips is perpendicular to the central axis of the laser resonator; a strip gap is formed between the first strips. Specifically, the periods of the second Bragg array A204A, the second Bragg array B204B, and the first Bragg array 202B are all equal; the periods of the second Bragg array A204A and the second Bragg array B204B are the sum of the width of the second strip and the width of the second groove; the period of the first Bragg array 202B is the sum of the width of the first strip and the strip gap.

[0077] Specifically, the period of the first Bragg array 202B is d = m * λ / (2 * n eff ); m is the diffraction order of the first Bragg array 202B, n effλ is the effective refractive index of the laser resonant cavity; λ is the operating wavelength of the laser's master mode. The thickness of the dielectric isolation layer 203 is no greater than 1 / 50 of λ. Furthermore, the spacing between the second Bragg array A204A and the second Bragg array B204B and the gain material layer 205 is no greater than 1 / 10 of λ. Specifically, the length of the second strip in the second Bragg array A204A and the second Bragg array B204B along its major axis is no less than 5λ.

[0078] The gap between the second Bragg array A204A and the waveguide ridge 202A is also known as the first gap 208A, and the gap between the second Bragg array B204B and the waveguide ridge 202A is also known as the second gap 208B. The first gap 208A and the second gap 208B are set to prevent the gain / loss Bragg array from contacting the P-type doped cladding buffer layer 202, so as to avoid short circuit.

[0079] Dielectric isolation layers 203 are provided between the second Bragg array A204A and the first Bragg array 202B on the same side, and between the second Bragg array B204B and the first Bragg array 202B on the same side, to avoid short circuits between the P electrode and the loss / gain conductive array during current injection; the thickness of the dielectric isolation layer 203 is no greater than 1 / 50 of the operating wavelength λ.

[0080] Each first Bragg array 202B includes a parallel groove (short amplitude modulation portion) and a first stripe (long amplitude modulation portion). The difference in modulation amplitude of the first Bragg array 202B is H202B, which is the height / thickness value of the first stripe protruding outward. The width of the first stripe in the modulation amplitude of the first Bragg array 202B is denoted as W202B. A P-type doped buffer layer 202, with a thickness not exceeding 1 / 20 of the operating wavelength, is retained below the first Bragg array 202B at a distance from the surface of the gain material layer 205. To prevent short circuits, a dielectric isolation layer 203 needs to be deposited first to isolate the loss / gain Bragg array 204 from the P-type doped buffer layer 202. The thickness of the dielectric isolation layer 203 on the first Bragg array 202B is H203. In this embodiment of the invention, the value of H203 does not exceed 1 / 50 of the operating wavelength. Subsequently, on both sides of the bottom of the first Bragg array 202B and above the dielectric isolation layer 203, a loss / gain Bragg array 204 (including a second Bragg array A204A and a second Bragg array B204B) is deposited. The period of this loss / gain Bragg array 204 is P204 (the period of the second Bragg array A204A corresponds to P204A, and the period of the second Bragg array B204B corresponds to P204B), and the width of the cell structure is W204 (the width of the second Bragg array A204B is W204). The width of array A is W204A, and the width of the second Bragg array B204B is W204B. The lateral length of the unit structure is L204 (the lateral length of the second Bragg array A204A is L204A, and the lateral length of the second Bragg array B204B is L204B). The height / thickness of the unit structure is H204 (the thickness of the second Bragg array A204A is H204A, and the thickness of the second Bragg array B204B is H204B). In principle, the second Bragg array A204A and the second Bragg array B204B have the same physical parameters, but in actual implementation, there may be some errors. The period P202B of the first Bragg array 202B has the same value as the period P204 of the loss / gain Bragg array, and the phase difference between the two Bragg arrays is denoted as Φ202-204.

[0081] The real modulation amplitude of the first Bragg array 202B is denoted as H202B, and the imaginary modulation amplitude of the loss / gain Bragg array is denoted as H204. By adjusting the real modulation amplitude H202B, the imaginary modulation amplitude H204, and the phase difference Φ202-204 between the two arrays, the complex coupling coefficients between the modes of the complex coupled distributed feedback (DFB) resonator composed of dual Bragg arrays can be precisely controlled, thereby achieving effective adjustment of the optical field and modes within the resonator. Through the above adjustments, a single-frequency mode with low loss, high transmission, and narrow linewidth characteristics is finally selected. When current is injected into the laser through the P-type metal electrode 201 and the N-type metal electrode 207, and the current density of the laser reaches a state above the threshold, the laser can achieve a stable single-frequency laser output. For specific control methods in this embodiment, please refer to Embodiment 1.

[0082] Example 3

[0083] The laser resonator in this embodiment corresponds to the third configuration. For example... Figure 9 As shown, the laser resonant cavity includes a gain material layer 303, a P-type doped cladding buffer layer 302 disposed above the gain material layer 303, and a waveguide ridge 302A with a central ridge formed by etching the P-type doped cladding buffer layer 302. A dielectric isolation layer 304 is disposed on the surface of the remaining etched area of ​​the waveguide ridge 302A, and the top surface of the dielectric isolation layer 304 is planar. A second doped cladding buffer layer is disposed below the gain material layer 303. A first Bragg array 302B is disposed on the dielectric isolation layer 304 on the surface of the remaining etched area of ​​the waveguide ridge 302A. The first Bragg array 302B is a lossless Bragg array. A second Bragg array is disposed on the dielectric isolation layer 304. The waveguide ridge 302A has a first electrode on its top surface and a second electrode on its bottom surface. A dielectric isolation layer 304 isolates the first doped buffer layer from the second Bragg array. A dielectric isolation layer 304 is provided on the remaining etched area of ​​the waveguide ridge 302A, and the top surface of the dielectric isolation layer 304 is planar. A second Bragg array A305A and a second Bragg array B305B are respectively provided on the two dielectric isolation layers 304. Both the second Bragg array A305A and the second Bragg array B305B are loss / gain Bragg arrays.

[0084] In this embodiment, a first Bragg array 302B is respectively disposed on the remaining etched areas on both sides of the two waveguide ridges, as shown in the specific structure. Figure 9As shown. The first Bragg array 302B is disposed on the remaining etched areas on both sides of the waveguide ridge; the top surfaces of the remaining etched areas on both sides of the waveguide ridge are etched inwards to form multiple independent and parallel first stripes as the first Bragg array 302B; stripe gaps are formed between the first stripes; a gain groove is formed by inward recessing the gain material layer 303 at a position corresponding to the stripe gap; the bottom surface of the dielectric isolation layer 304 is embedded in the gain groove. The portion of the dielectric isolation layer 304 embedded downward into the gain material layer 303 is called the dielectric isolation layer embedding portion 304A; the portion of the gain material layer 303 located below the first strip protrudes upward to form the gain material layer protrusion portion 303A, which provides support for the first strip from below. The first strip is sandwiched between the dielectric isolation layer 304 and the gain material layer protrusion portion 303A, and the side of the dielectric isolation layer 304 that contacts the gain material layer 303 forms a toothed interlaced structure. The width W303A of the gain material layer protrusion portion 303A is equal to the width W302B of the first strip. H303A is the distance between the top surface of the gain material layer protrusion portion 303A and the bottom surface of the gain material layer 303, which is also the thickness of the gain material layer 303. Waveguide ridges 302A can be etched from top to bottom in the P-doped semiconductor layer. The size of the waveguide ridges 302A is matched with the active layer to achieve a lateral fundamental mode operation. Then, two etched remaining regions are formed on both sides of the waveguide ridges 302A. Further etching is performed on the surface of the etched remaining regions on both sides of the waveguide ridges to obtain the first Bragg array 302B.

[0085] In this embodiment, the N-type metal electrode 307 and the N-type doped coating buffer layer 306 can be replaced with the P-type metal electrode and the P-type doped coating buffer layer 302; the P-type doped coating buffer layer 302 and the P-type metal electrode 301 can be replaced with the N-doped coating buffer layer and the N-type metal electrode respectively. Interchanging the polarities does not affect the function of the laser resonator in this application.

[0086] In a more specific embodiment, the unit structures of the second Bragg array A305A and the second Bragg array B305B are both composed of parallel second strips arranged together, with a second groove formed between the second strips; the long axis of the second strips is perpendicular to the central axis of the laser resonator; the unit structure of the first Bragg array 302B is composed of first strips disposed on the dielectric isolation layer of the etched remaining area surface layer on both sides of the waveguide ridge; the first strips are arranged in parallel and the long axis of the first strips is perpendicular to the central axis of the laser resonator; a strip gap is formed between the first strips. Specifically, the periods of the second Bragg array A305A, the second Bragg array B305B, and the first Bragg array 302B are all equal; the periods of the second Bragg array A305A and the second Bragg array B305B are the sum of the width of the second strip and the width of the second groove; the period of the first Bragg array 302B is the sum of the width of the first strip and the strip gap.

[0087] Specifically, the period of the first Bragg array 302B is d = m * λ / (2 * n eff ); m is the diffraction order of the first Bragg array 302B, n eff λ is the effective refractive index of the laser resonant cavity; λ is the operating wavelength of the laser's master mode. The thickness of the dielectric isolation layer 304 is no greater than 1 / 50 of λ. Furthermore, the spacing between the second Bragg array A305A and the second Bragg array B305B and the gain material layer 303 is no greater than 1 / 10 of λ. Specifically, the length of the second strip in the second Bragg array A305A and the second Bragg array B305B along its major axis is no less than 5λ.

[0088] The gap between the second Bragg array A305A and the waveguide ridge 302A is also known as the first gap 308A, and the gap between the second Bragg array B305B and the waveguide ridge 302A is also known as the second gap 308B. The first gap 308A and the second gap 308B are set to prevent the gain / loss Bragg array from contacting the P-type doped cladding buffer layer 302, so as to avoid short circuit.

[0089] Dielectric isolation layers 304 are provided between the second Bragg array A305A and the first Bragg array 302B on the same side, and between the second Bragg array B305B and the first Bragg array 302B on the same side, to avoid short circuits between the P electrode and the loss / gain conductive array during current injection; the thickness of the dielectric isolation layer 304 is no greater than 1 / 50 of the operating wavelength λ.

[0090] Each first Bragg array 302B includes a stripe gap (short amplitude modulation portion) and a first stripe (long amplitude modulation portion). The difference in modulation amplitude of the first Bragg array 302B is H302B, which is the height / thickness value of the first stripe protruding outward. The width of the first stripe in the modulation amplitude of the first Bragg array 302B is denoted as W302B. A P-type doped cladding buffer layer 302, with a thickness not exceeding 1 / 20 of the operating wavelength, is retained below the first Bragg array 302B at a distance from the surface of the gain material layer 303. To prevent short circuits, a dielectric isolation layer 304 needs to be deposited first to isolate the loss / gain Bragg array 305 from the P-type doped cladding buffer layer 302. The thickness of the dielectric isolation layer 304 on the first Bragg array 302B is H304. In this embodiment of the invention, the value of H304 does not exceed 1 / 50 of the operating wavelength. Subsequently, on both sides of the bottom of the first Bragg array 302B and above the dielectric isolation layer 304, a loss / gain Bragg array 305 (including a second Bragg array A305A and a second Bragg array B305B) is deposited. The period of this loss / gain Bragg array 305 is P305 (the period of the second Bragg array A305A corresponds to P305A, and the period of the second Bragg array B305B corresponds to P305B), the width of the cell structure is W305 (the width of the second Bragg array A305A corresponds to W305A, and the width of the second Bragg array B305B corresponds to W305B), and the lateral length of the cell structure is L305. (The lateral length of the second Bragg array A305A is L305A, and the lateral length of the second Bragg array B305B is L305B). The height / thickness of the unit structure is H305 (the thickness of the second Bragg array A305A is H305A, and the thickness of the second Bragg array B305B is H305B). In principle, the second Bragg array A305A and the second Bragg array B305B have the same physical parameters, but in actual implementation, there may be some errors. The period P302B of the first Bragg array 302B (the period P302B is twice the width W303A) has the same value as the period P305 of the loss / gain Bragg array. The phase difference between the two Bragg arrays is denoted as Φ305-303.

[0091] The real modulation amplitude of the first Bragg array 302B is denoted as H302B, and the imaginary modulation amplitude of the loss / gain Bragg array is denoted as H305. By adjusting the real modulation amplitude H302B, the imaginary modulation amplitude H305, and the phase difference Φ305-303 between the two arrays, the complex coupling coefficients between the modes of the complex coupled distributed feedback (DFB) resonator composed of dual Bragg arrays can be precisely controlled, thereby achieving effective adjustment of the optical field and modes within the resonator. Through the above adjustments, a single-frequency mode with low loss, high transmission, and narrow linewidth characteristics is finally selected. When current is injected into the laser through the P-type metal electrode 301 and the N-type metal electrode 307, and the current density of the laser reaches a state above the threshold, the laser can achieve a stable single-frequency laser output. For specific control methods in this embodiment, please refer to Embodiment 1.

[0092] The laser resonator in this embodiment can be assembled to form a high-performance, anti-interference single-frequency semiconductor laser. High-performance, anti-interference single-frequency semiconductor lasers, with their ultra-narrow linewidth, high frequency stability, and strong anti-interference characteristics, play a crucial role in many high-tech fields. In the field of optical communication, it serves as the core light source for coherent optical communication systems, enabling high-speed data transmission exceeding 100Gbps. Its anti-interference capabilities ensure stable operation in complex electromagnetic environments. In precision measurement, it provides sub-millimeter-level measurement accuracy for applications such as lidar, gravitational wave detection (e.g., LIGO, Laser Interferometer Gravitational-Wave Observatory), and satellite ranging. Its resistance to temperature drift and mechanical vibration ensures measurement reliability. In the field of quantum technology, as a light source for quantum key distribution (QKD) and cold atom confinement, its frequency stability and resistance to environmental interference directly determine system performance. In defense and military applications, it is used in missile guidance, laser weapons, and anti-jamming communication systems, with its strong resistance to electromagnetic interference meeting the demands of harsh battlefield environments. In industrial inspection, it provides a stable light source for semiconductor lithography and wafer inspection, with its resistance to power fluctuations and thermal noise ensuring consistency in manufacturing processes. In medical diagnostics, it supports optical coherence tomography (OCT). High-end medical devices such as Tomography and flow cytometry utilize the laser's ability to resist interference from biological tissue scattering, improving diagnostic accuracy. These applications are attributed to the laser's distributed feedback (DFB) or distributed Bragg reflection (DBR) structure, precise temperature control technology, and innovative anti-interference design, which enable it to maintain high performance while possessing excellent environmental adaptability, making it a key component in modern optoelectronic systems.

[0093] This invention provides an electrically pumped complex-coupled distributed feedback laser resonator and laser. The laser resonator includes a gain material layer; a first doped cladding buffer layer is disposed above the gain material layer, and the first doped cladding buffer layer is etched to form a waveguide ridge with a central ridge. The surface of the remaining etched areas on both sides of the waveguide ridge is provided with a dielectric isolation layer, and the top surface of the dielectric isolation layer is planar; a second doped cladding buffer layer is disposed below the gain material layer; a first Bragg array is provided on the side walls of the waveguide ridge or on the surface of the remaining etched areas on both sides of the waveguide ridge; a second Bragg array is provided on the dielectric isolation layer; a first electrode is provided on the top surface of the waveguide ridge; and a second electrode is provided on the bottom surface of the second doped cladding buffer layer. The aforementioned laser resonant cavity, by adjusting the amplitude and phase difference of the Bragg array, can precisely control the complex coupling coefficients between modes within the resonant cavity of a distributed feedback laser composed of dual Bragg arrays, thereby obtaining a single-frequency laser with low loss, high transmission, and narrow linewidth characteristics. When current is injected through N-type and P-type metal electrodes and the current density of the laser reaches a threshold or higher, the laser can achieve stable single-frequency laser output and has strong resistance to external echoes.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An electrically pumped, doubly coupled distributed feedback laser resonator, characterized in that, The laser resonant cavity includes a gain material layer; The first doped cladding buffer layer is disposed above the gain material layer. The first doped cladding buffer layer is etched to form a waveguide ridge with a raised center. The surface of the remaining etched areas on both sides of the waveguide ridge is provided with a dielectric isolation layer. The top surface of the dielectric isolation layer is a plane. The second doped coating buffer layer is disposed below the gain material layer; The waveguide ridge has a first Bragg array on the surface of the two side walls or the remaining etched areas on both sides of the waveguide ridge; the first Bragg array is a non-destructive Bragg array. A second Bragg array is provided on the dielectric isolation layer; the second Bragg array is a loss / gain Bragg array. The top surface of the waveguide ridge is provided with a first electrode; the bottom surface of the second doped cladding buffer layer is provided with a second electrode. The dielectric isolation layer isolates the first doped coating buffer layer from the second Bragg array; The first Bragg array and the second Bragg array are provided with a preset displacement of up to 2π.

2. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 1, characterized in that, The refractive index of the gain material layer is greater than that of the first doped buffer layer and the second doped buffer layer, and the gain material layer is prepared from a material that provides interband recombination or subband transition.

3. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 1, characterized in that, The distance between the bottom of the waveguide ridge and the gain material layer is no greater than 1 / 20 of λ, where λ is the operating wavelength of the laser master mode.

4. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 3, characterized in that, The period of the first Bragg array and the second Bragg array is d, d = m * λ / (2 * n eff ); m is the diffraction order of the Bragg array, n eff is the effective refractive index of the laser resonant cavity.

5. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 1, characterized in that, The first Bragg array is disposed on both sides of the waveguide ridge. The first doped cladding buffer layer is etched from top to bottom based on the Bragg array mask to obtain a waveguide ridge with Bragg structure on both sides. Alternatively, the first Bragg array is disposed on the surface layer of the remaining etched area on both sides of the waveguide ridge, and a planar Bragg structure is fabricated with the centerline of the waveguide ridge as the axis of symmetry as the first Bragg array. The unit structure of the first Bragg array is composed of first strips; the first strips are arranged in parallel and the long axis of the first strips is perpendicular to the long axis of the waveguide ridge; a strip gap is formed between the first strips; The unit structure of the first Bragg array is composed of a first strip, the length of the minor axis of the first strip is less than the Bragg period d, and the length of the first strip along the major axis is not less than 5λ.

6. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 1, characterized in that, The thickness of the dielectric isolation layer is no greater than 1 / 50 of λ; the refractive index of the dielectric isolation layer is less than the refractive indices of the first doped buffer layer and the second doped buffer layer.

7. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 5, characterized in that, The second Bragg array is positioned on the dielectric isolation layers on both sides of the waveguide ridge with the centerline of the waveguide ridge as the axis of symmetry. The unit structure of the second Bragg array is composed of parallel second strips. The short axis length of the second strip is less than the Bragg period d, and the length of the second strip along the long axis is not less than 5λ.

8. The electrically pumped complex-coupled distributed feedback laser resonator according to any one of claims 1-7, characterized in that, The unit structure shape of the first Bragg array and the second Bragg array is any one of cuboid, sawtooth, sine, and cosine shapes, or a combination of multiple shapes.

9. The electrically pumped complex-coupled distributed feedback laser resonator according to claim 1, characterized in that, The second electrode is an N-type metal electrode, the second doped coating buffer layer is an N-type doped coating buffer layer, the first doped coating buffer layer is a P-type doped coating buffer layer, and the first electrode is a P-type metal electrode; Alternatively, the second electrode may be a P-type metal electrode, the second doped buffer layer may be a P-type doped buffer layer, the first doped buffer layer may be an N-type doped buffer layer, and the first electrode may be an N-type metal electrode.

10. A laser, characterized in that, The laser includes an electrically pumped complex-coupled distributed feedback laser resonator as described in any one of claims 1-9.

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