High-speed surface-emitting laser and method for manufacturing the same

Abstract

The present invention provides a high-speed surface-emitting laser and a method for manufacturing the same. The high-speed surface-emitting laser includes an N-type substrate, an N-type contact layer, an N-type confinement layer, a lower oxidizable layer, an active layer, an upper oxidizable layer, a P-type confinement layer, and a P-type contact layer, which are sequentially fabricated from bottom to top. A topologically non-trivial state photonic crystal and a topologically trivial state photonic crystal are etched in the P-type contact layer and a part of the P-type confinement layer or in the P-type confinement layer. The topologically non-trivial state photonic crystal is surrounded by the topologically trivial state photonic crystal. The topologically non-trivial state photonic crystal forms two resonant cavities and a coupling channel for coupling the two resonant cavities. By means of the photon-photon resonance effect of the two resonant cavities, the present invention can break through the relaxation oscillation frequency limitation caused by the carrier-photon resonance generated by the resonant cavity of the surface-emitting laser, thereby expanding the bandwidth and improving the modulation bandwidth of the surface-emitting laser.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor lasers, and particularly relates to a high-speed surface-emitting laser and a preparation method thereof. Background Art

[0002] High-speed surface-emitting lasers (SELs) are important light sources in the field of optical interconnection. The optical interconnection technology based on high-speed vertical-cavity surface-emitting lasers (VCSELs) and multimode optical fibers (MMFs) has the advantages of low cost and low energy consumption, and is developing towards higher speeds and longer distances. Increasing the modulation bandwidth of VCSELs can increase the VCSEL-MMF data transmission rate. Single-mode VCSELs can reduce modal dispersion and increase the VCSEL-MMF transmission distance, enabling the VCSEL-based optical interconnection technology to be used not only for data transmission within short-distance data centers but also for data transmission between longer-distance data centers.

[0003] Increasing the modulation bandwidth of VCSELs can be achieved by increasing the optical confinement factor and reducing the active region volume. The active region of a VCSEL is related to the cavity length and aperture of the VCSEL. Currently, the cavity length of data communication VCSELs is usually half of the wavelength, and the cavity length of VCSELs cannot be further reduced. Although the aperture of VCSELs can be reduced to increase the modulation bandwidth and achieve single-mode operation simultaneously, reducing the aperture of VCSELs will lead to problems such as an increase in resistance and a decrease in output power.

[0004] Photonic crystal surface-emitting semiconductor lasers (PCSELs) achieve laser oscillation through photonic crystal band-edge modes and realize single-mode surface emission output of the laser through Bragg diffraction. Compared with VCSELs, PCSELs have lower absorption losses and series resistances, and at the same time have a higher optical confinement factor, which is beneficial to increasing the modulation bandwidth of the laser. However, the realization of laser oscillation in PCSELs requires a relatively large resonator size, so the active region volume is large, which has a negative impact on increasing the modulation bandwidth of PCSELs.

[0005] Professor Renmin Ma of Peking University extended the topological edge state to the topological bulk state, constructed a laser cavity through two types of photonic crystals with topological trivial states and topological non-trivial states, and realized laser oscillation through a novel energy band inversion optical field confinement effect at their interface. This topological bulk state-based PCSEL not only has the advantages of high confinement factor and low resistance of traditional PCSELs, but also can achieve single-mode output of the laser based on the topological energy band inversion optical field confinement effect. However, the development of topological bulk state-based PCSELs has encountered bottlenecks and cannot further increase the bandwidth. Summary of the Invention

[0006] The object of the present invention is to overcome the defects of the prior art and propose a high-speed surface-emitting laser and a preparation method thereof, which can increase the relaxation oscillation frequency of the surface-emitting laser, ensure the single-mode characteristic at the same time, and further improve the modulation bandwidth of the surface-emitting laser.

[0007] To achieve the above object, the present invention adopts the following specific technical solutions:

[0008] The high-speed surface-emitting laser provided by the present invention includes an N-type substrate, an N-type contact layer, an N-type confinement layer, an active layer, a P-type confinement layer, and a P-type contact layer prepared in sequence from bottom to top. A topologically non-trivial state photonic crystal and a topologically trivial state photonic crystal are etched in the P-type contact layer and part of the P-type confinement layer or in the P-type confinement layer. The topologically non-trivial state photonic crystal is surrounded by the topologically trivial state photonic crystal. The topologically non-trivial state photonic crystal forms two resonant cavities and a coupling channel for coupling the two resonant cavities.

[0009] Preferably, an oxidizable layer is prepared between the active layer and the N-type confinement layer and / or between the active layer and the P-type confinement layer. The oxidizable layer includes an oxidized part located at the edge and an unoxidized part located at the center. The oxidized part forms an insulating material after oxidation, so that the unoxidized part forms an aperture for current flow.

[0010] Preferably, the topologically non-trivial state photonic crystal and the topologically trivial state photonic crystal respectively include unit cells arranged in a honeycomb lattice periodically with the same lattice constant. Nanopores with a rotationally symmetric distribution are formed inside the unit cells. For the topologically non-trivial state photonic crystal, the distance between the center of the nanopore and the center of the unit cell is greater than one-third of the lattice constant of the photonic crystal. For the topologically trivial state photonic crystal, the distance between the center of the nanopore and the center of the unit cell is less than one-third of the lattice constant of the photonic crystal.

[0011] Preferably, the nanopores are circular, triangular or square. When the nanopores are circular or triangular, the number of nanopores in each unit cell is six, and the corresponding unit cell is a regular hexagon. When the nanopores are square, the number of nanopores in each unit cell is four, and the corresponding unit cell is a square.

[0012] Preferably, a dielectric material with a refractive index less than that of the surrounding medium is filled in the nanopores.

[0013] Preferably, both the N-type contact layer and the P-type contact layer are doped layers, and the doping concentration of the doping layer exceeds 5×10 18 cm -3 。

[0014] A preparation method of a high-speed surface-emitting laser provided by the present invention is used to prepare the above high-speed surface-emitting laser, and includes the following steps:

[0015] S1, sequentially growing an N-type contact layer, an N-type confinement layer, an active layer, a P-type confinement layer, and a P-type contact layer on an N-type substrate;

[0016] S2, etching from the P-type contact layer downward to the P-type confinement layer to form a topological non-trivial state photonic crystal and a topological trivial state photonic crystal; wherein the topological non-trivial state photonic crystal is surrounded by the topological trivial state photonic crystal to form two resonant cavities and a coupling channel coupling the two resonant cavities;

[0017] S3, etching from the P-type contact layer down to the N-type contact layer to form a mesa at a position avoiding the topological non-trivial state photonic crystal and the topological trivial state photonic crystal;

[0018] S4, depositing a layer of electrode material on the P-type contact layer on the mesa to form a P-side electrode, and depositing a layer of electrode material on the N-type contact layer outside the mesa to form an N-side electrode;

[0019] S5. Depositing a planarization material layer at a position outside the mesa, avoiding the N-side electrode, to form a planarization material layer at the same height as the P-side electrode;

[0020] S6. Using a planarization material layer, the P-side electrode and the N-side electrode are brought to the same height to form coplanar electrodes.

[0021] Preferably, in step S1, an oxidizable layer is prepared between the active layer and the N-type confinement layer and / or between the active layer and the P-type confinement layer, and the oxidizable layer is formed into an insulating material by oxidizing the edge portion, while the central unoxidized portion forms an aperture for current flow.

[0022] Another method for preparing a high-speed surface-emitting laser provided by the present invention is used to prepare the above-mentioned high-speed surface-emitting laser, comprising the following steps:

[0023] S1, sequentially growing an N-type contact layer, an N-type confinement layer, an active layer, and a P-type confinement layer on an N-type substrate;

[0024] S2. Etching downward in the P-type confinement layer to a position close to the active layer to form a topological non-trivial state photonic crystal and a topological trivial state photonic crystal; wherein the topological non-trivial state photonic crystal is surrounded by the topological trivial state photonic crystal to form two resonant cavities and a coupling channel coupling the two resonant cavities;

[0025] S3, growing a P-type contact layer on the P-type confinement layer;

[0026] S4, etching from the P-type contact layer downward to the N-type confinement layer to form a mesa at a position avoiding the topological non-trivial state photonic crystal and the topological trivial state photonic crystal;

[0027] S5. Deposit an electrode material layer on the P-type contact layer on the mesa to form a P-side electrode, and deposit an electrode material layer on the N-type confinement layer outside the mesa to form an N-side electrode;

[0028] S6. Deposit a planarization material layer at a position outside the mesa and avoiding the N-side electrode, with the same height as the P-side electrode;

[0029] S7. Use the planarization material layer to lead out the P-side electrode and the N-side electrode to the same height to form a coplanar electrode.

[0030] Preferably, in step S1, an oxidizable layer is prepared between the active layer and the N-type confinement layer and / or between the active layer and the P-type confinement layer. The oxidizable layer forms an insulating material through the oxidation of the edge part, and the unoxidized part in the center forms an aperture for current flow.

[0031] The present invention can achieve the following technical effects:

[0032] 1. Through the photon-photon resonance effect of the two resonant cavities, the relaxation oscillation frequency limit caused by the carrier-photon resonance generated by the resonant cavity of the surface-emitting laser can be broken through, thereby expanding the bandwidth and improving the modulation bandwidth of the surface-emitting laser.

[0033] 2. The insulating material formed after the oxidation of the oxidizable layer can limit the current, ensuring that the current flows more concentratedly through the active layer, making it easier for the active layer to lasing. Brief Description of the Drawings

[0034] Figure 1 is a schematic structural diagram of a high-speed surface-emitting laser provided in Embodiment 1 of the present invention;

[0035] Figure 2 is a schematic structural diagram of a photonic crystal structure provided in Embodiment 1 of the present invention;

[0036] Figure 3 is a schematic structural diagram of two resonant cavities and a coupling channel provided in Embodiment 1 of the present invention;

[0037] Figure 4 is a schematic diagram of the simulation result of setting a light source in one resonant cavity provided in Embodiment 1 of the present invention;

[0038] Figure 5 is a schematic diagram of the simulation result of setting light sources in both two resonant cavities provided in Embodiment 1 of the present invention;

[0039] Figures 6 - 13 is a schematic diagram of the dynamic preparation process of a high-speed surface-emitting laser provided in Embodiment 2 of the present invention;

[0040] Figures 14 - 16It is a schematic diagram of the dynamic preparation process of a high-speed surface-emitting laser according to Embodiment 3 of the present invention.

[0041] The reference numerals therein include: N-type substrate 11, N-type contact layer 12, N-type confinement layer 13, lower oxidizable layer 14, active layer 15, upper oxidizable layer 16, P-type confinement layer 17, P-type contact layer 18, topologically non-trivial state photonic crystal 21, topologically trivial state photonic crystal 22, first unit cell 23, second unit cell 24, main cavity 25, coupled cavity 26, coupling channel 27, energy band boundary 31, mesa boundary 32, mesa 41, oxidized portion 51, unoxidized portion 52, P-side electrode 61, N-side electrode 62, planarization material layer 71, coplanar electrode 81. Detailed implementation manners

[0042] In the following, embodiments of the present invention will be described with reference to the drawings. In the following description, the same modules are denoted by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, their detailed descriptions will not be repeated.

[0043] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention.

[0044] Embodiment 1

[0045] Figure 1 It shows the structure of a high-speed surface-emitting laser according to Embodiment 1 of the present invention.

[0046] As Figure 1 shown, the high-speed surface-emitting laser provided in Embodiment 1 of the present invention includes an N-type substrate 11, an N-type contact layer 12, an N-type confinement layer 13, a lower oxidizable layer 14, an active layer 15, an upper oxidizable layer 16, a P-type confinement layer 17, and a P-type contact layer 18 sequentially prepared from bottom to top. In the P-type contact layer 18 and part of the P-type confinement layer 17 or within the P-type confinement layer 17, a photonic crystal structure is constructed by etching nanopores. The photonic crystal structure includes a topologically non-trivial state photonic crystal 21 and a topologically trivial state photonic crystal 22.

[0047] There are two ways to construct the topologically non-trivial state photonic crystal 21 and the topologically trivial state photonic crystal 22. One way is to etch from the P-type contact layer 18 down to the P-type confinement layer 17 to form the photonic crystal structure; the other way is to first etch to form the photonic crystal structure after growing the P-type confinement layer 17 in a single epitaxial process, and then apply a regrowth process to generate the P-type contact layer 18 to form a buried photonic crystal structure.

[0048] Figure 2Shows a schematic structural diagram of a photonic crystal structure provided according to Embodiment 1 of the present invention.

[0049] As Figure 2 shown, the topologically non-trivial state photonic crystal 21 includes a plurality of first unit cells 23 periodically arranged in a honeycomb lattice with the same lattice constant, and the topologically trivial state photonic crystal 22 includes a plurality of second unit cells 24 periodically arranged in a honeycomb lattice with the same lattice constant. The outer edges of the first unit cell 23 and the second unit cell 24 are both regular polygons. There are nanopores with rotationally symmetric distribution inside the first unit cell 23 and the second unit cell 24. The nanopores are circular, equilateral triangular or square, and no nanopores are prepared at the centers of the first unit cell 23 and the second unit cell 24.

[0050] Due to the different distances from the nanopores to the centers of the unit cells, two different energy band structures of dipole mode and quadrupole mode are formed; when the distance between the center of the nanopore and the center of the first unit cell 23 is less than one-third of the photonic crystal lattice constant, there is no band inversion between the dipole and quadrupole modes, constituting a topologically trivial state photonic crystal; 61 body; the etched topologically non-trivial state photonic crystal 21 is surrounded by the topologically trivial state photonic crystal 22, and the interface between the two constitutes an energy band boundary 31, and the energy band boundary 31 constitutes a closed curve; due to the different energy band structures at both ends of the energy band boundary 31, photons with frequencies near the center of the Brillouin zone will be reflected at the boundary, thus forming a resonant cavity within the closed energy band boundary 31, and the light field is transversely restricted in this way. The light wave is effectively restricted transversely by the photonic crystal structure, coupled to the vertical direction through Bragg diffraction and resonates to achieve single-mode lasing, and the high-speed surface-emitting laser has vertical emission characteristics.

[0051] When the outer edges of the unit cells (the first unit cell 23 and the second unit cell 24) are both regular hexagons, the shapes of the nanopores inside the unit cells are circular or triangular, and the number is six. Six circular nanopores or triangular nanopores are rotationally symmetrically distributed along the center of the unit cell to form the unit cell.

[0052] When the outer edges of the unit cells are both regular quadrilaterals, the shapes of the nanopores inside the unit cells are square, and the number is four. Four square nanopores are rotationally symmetrically distributed along the center of the unit cell to form the unit cell.

[0053] Regardless of the shape of the nanopores, a dielectric material with a refractive index less than that of the surrounding medium can be filled in the nanopores to change the refractive index difference from the surrounding medium.

[0054] The lower oxidizable layer 14 and the upper oxidizable layer 16 include an oxidized portion 51 at the edge and an unoxidized portion 52 at the center. The oxidized portion 51 contains a high-aluminum component and forms an insulating material after oxidation. The oxidized oxidized portion 51 surrounds the unoxidized portion at the center to form an aperture through which current can flow.

[0055] When current is injected into the high-speed surface-emitting laser, due to the limitation of the lower oxidizable layer 14 and the upper oxidizable layer 16, the current flows more concentratedly through the active layer 15, and the current density of the active layer 15 is higher, making it easier for the active layer 15 to lasing.

[0056] Figure 1 The situation of preparing oxidizable layers on both the upper and lower sides of the active layer 15 is shown, but the present invention is not limited to the above situation. It is also possible to prepare an oxidizable layer only on the upper side or the lower side of the active layer 15 to limit the current, and the number of oxidizable layers can be one layer or multiple layers.

[0057] The N-type contact layer 12 and the P-type contact layer 18 can be doped layers in contact with the P-side electrode and the N-side electrode, and the doping concentration of the doped layer exceeds 5×10 18 cm -3 , to achieve good ohmic contact.

[0058] Figure 3 Shows the structure of two resonant cavities and a coupling channel provided according to Embodiment 1 of the present invention.

[0059] As Figure 3 shown, two identical resonant cavities are constructed laterally, one as the main cavity 25 and the other as the coupling cavity 26. A coupling channel 27 is formed between the main cavity 25 and the coupling cavity 26 through a topologically non-trivial state photonic crystal 21, so that the confined quadrupole mode can form a coupling between the main cavity 25 and the coupling cavity 26 through the coupling channel 27. Through the photon-photon resonance effect between the main cavity 25 and the coupling cavity 26, the relaxation oscillation frequency limit caused by the carrier-photon resonance generated by the resonant cavity of the surface-emitting laser can be broken through, thereby expanding the bandwidth and improving the modulation bandwidth of the surface-emitting laser.

[0060] In order to keep the currents of the main cavity 25 and the coupling cavity 26 independent and allow light to pass freely, it is necessary to ensure that there is no conduction between the main cavity 25 and the coupling cavity 26. Generally, a high-resistance region is realized at the coupling channel 27 by proton injection to achieve the purpose of electrical insulation.

[0061] Figure 4 Is the simulation result of setting a light source in a coupling cavity provided according to Embodiment 1 of the present invention.

[0062] As Figure 4 shown, through simulation, it can be found that when a light source is set in a main cavity, both the main cavity and the coupling cavity achieve single-mode, and the coupling channel between them does not affect the mode distribution of the main cavity, and still can ensure good single-mode characteristics.

[0063] Figure 5Shows the simulation results of setting light sources in both of the two coupled cavities according to Embodiment 1 of the present invention.

[0064] As Figure 5 shown, by setting light sources in both the main cavity and the coupled cavity, the single-mode property of the main cavity remains intact, and the electric field distribution is significantly enhanced compared with the case of setting a light source in a single cavity.

[0065] Embodiment 2

[0066] Embodiment 2 of the present invention provides a preparation method of a high-speed surface-emitting laser for the high-speed surface-emitting laser of Embodiment 1.

[0067] Figures 6 - 13 Respectively show the dynamic preparation process of the high-speed surface-emitting laser provided according to Embodiment 2 of the present invention.

[0068] As Figures 6 - 13 shown, the preparation method of the high-speed surface-emitting laser provided in Embodiment 2 of the present invention includes the following steps:

[0069] S1. Sequentially grow an N-type contact layer 12, an N-type confinement layer 13, a lower oxidizable layer 14, an active layer 15, an upper oxidizable layer 16, a P-type confinement layer 17, and a P-type contact layer 18 on an N-type substrate 11.

[0070] S2. Etch from the P-type contact layer 18 down to the P-type confinement layer 17 to form a topologically non-trivial state photonic crystal 21 and a topologically trivial state photonic crystal 22.

[0071] The topologically non-trivial state photonic crystal 21 is surrounded by the topologically trivial state photonic crystal 22 to form two resonant cavities and a coupling channel for coupling the two resonant cavities.

[0072] The topologically non-trivial state photonic crystal 21 surrounded by the topologically trivial state photonic crystal 22 has been described in detail in Embodiment 1, so it will not be elaborated here.

[0073] The confined quadrupole mode can form coupling between the two resonant cavities through the coupling channel. Through the photon-photon resonance effect between the two resonant cavities, the relaxation oscillation frequency limit caused by the carrier-photon resonance generated by the resonant cavity of the surface-emitting laser can be broken through, thereby expanding the bandwidth and improving the modulation bandwidth of the surface-emitting laser.

[0074] [[ID=3८]]To keep the currents of the two resonant cavities independent and allow light to pass freely, it is necessary to ensure that there is no conduction between the two resonant cavities. Therefore, before etching to form the topologically non-trivial state photonic crystal 21 and the topologically trivial state photonic crystal 22, a high-resistance region is realized at the coupling channel by means of proton implantation to achieve electrical insulation between the two resonant cavities.

[0075] S3. Avoid the positions of the topological non-trivial state photonic crystal 21 and the topological trivial state photonic crystal 22, and etch down from the P-type contact layer 18 to the N-type confinement layer 13 at the mesa boundary 32 to form a mesa 41 that exposes the lower oxidizable layer 14 and the upper oxidizable layer 16.

[0076] The exposed lower oxidizable layer 14 and the upper oxidizable layer 16 form an insulating material by oxidizing the edge portions, while the unoxidized central portion forms an aperture for current flow. When current is injected into the high-speed surface-emitting laser, due to the confinement of the lower oxidizable layer 14 and the upper oxidizable layer 16, the current flows more concentratedly through the active layer 15, and the current density of the active layer 15 is higher, making it easier for the active layer 15 to lasing.

[0077] Of course, the present invention can also fabricate an oxidizable layer only on the upper side or the lower side of the active layer 15 to restrict the current, and the number of oxidizable layers can be one or more.

[0078] S4. Deposit an electrode material on the P-type contact layer 18 on the mesa 41 to form a P-side electrode 61, and deposit an electrode material on the N-type confinement layer 13 outside the mesa 41 to form an N-side electrode 62.

[0079] S5. Deposit a planarization material layer 71 at a position outside the mesa 41 that avoids the N-side electrode 62 and has the same height as the P-side electrode 61.

[0080] The planarization material layer 71 needs to avoid covering the N-side electrode 62 to make the surface of the high-speed surface-emitting laser flat.

[0081] S6. Use the planarization material layer 71 to lead out the P-side electrode 61 and the N-side electrode 62 to the same height to form a coplanar electrode 81.

[0082] Lead out the P-side electrode 61 and the N-side electrode 62 to the same height to achieve current injection.

[0083] If etching from the P-type contact layer 18 to a position close to the active layer 15, the etching depth is too deep, which affects the current distribution, makes the current uneven, and leads to an increase in resistance. Usually, the maximum output optical power is measured between the etching depth and the diffraction efficiency.

[0084] Embodiment 3

[0085] Embodiment 3 of the present invention provides another method for fabricating a high-speed surface-emitting laser for the high-speed surface-emitting laser of Embodiment 1.

[0086] Figures 14 - 16 Respectively show the dynamic fabrication process of the high-speed surface-emitting laser provided according to Embodiment 3 of the present invention.

[0087] As Figures 14 - 16As shown in the figure, the method for preparing a high-speed surface-emitting laser provided in Embodiment 3 of the present invention includes the following steps:

[0088] S1. An N-type contact layer 12, an N-type confinement layer 13, a lower oxidizable layer 14, an active layer 15, an upper oxidizable layer 16, and a P-type confinement layer 17 are sequentially grown on an N-type substrate 11.

[0089] S2. A topologically non-trivial state photonic crystal 21 and a topologically trivial state photonic crystal 22 are formed by etching downward in the P-type confinement layer 17 to a position close to the active layer 15.

[0090] S3. A P-type contact layer 18 is grown on the P-type confinement layer 17 by using a regrowth process.

[0091] The remaining steps are the same as S3 - S6 in Embodiment 2.

[0092] In this Embodiment 3, an oxidizable layer can also be prepared only on the upper side or the lower side of the active layer 15 to limit the current, and the number of oxidizable layers can be one or more.

[0093] In this Embodiment 3, etching is performed downward from the P-type confinement layer 17. Compared with Embodiment 2, the etching depth is shallower but closer to the active layer 15. Therefore, Embodiment 3 can make the light intensity at the photonic crystal structure stronger and at the same time obtain a higher vertical direction output optical power.

[0094] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0095] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0096] The above specific implementation manners of the present invention do not constitute a limitation to the protection scope of the present invention. Any other corresponding changes and deformations made according to the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A high-speed surface-emitting laser, comprising an N-type substrate, an N-type contact layer, an N-type confinement layer, an active layer, a P-type confinement layer, and a P-type contact layer sequentially fabricated from bottom to top. A topologically non-trivial state photonic crystal and a topologically trivial state photonic crystal are etched and formed within the P-type contact layer and a part of the P-type confinement layer or within the P-type confinement layer, and the topologically non-trivial state photonic crystal is surrounded by the topologically trivial state photonic crystal; characterized in that, The topologically non-trivial state photonic crystal forms two resonant cavities and a coupling channel for coupling the two resonant cavities; a high-resistance region is realized at the coupling channel by means of proton implantation.

2. The high-speed surface-emitting laser according to claim 1, wherein An oxidizable layer is prepared between the active layer and the N-type confinement layer and / or between the active layer and the P-type confinement layer. The oxidizable layer includes an oxidized portion at the edge and an unoxidized portion at the center. The oxidized portion forms an insulating material after oxidation, so that the unoxidized portion forms an aperture for current to flow through.

3. The surface-emitting laser with high speed according to claim 1, characterized in that, The topologically non-trivial state photonic crystal and the topologically trivial state photonic crystal respectively include unit cells arranged in a honeycomb lattice with the same lattice constant in a periodic manner. Nanopores with a rotationally symmetric distribution are formed inside the unit cells. For the topologically non-trivial state photonic crystal, the distance between the center of the nanopore and the center of the unit cell is greater than one-third of the lattice constant of the photonic crystal. For the topologically trivial state photonic crystal, the distance between the center of the nanopore and the center of the unit cell is less than one-third of the lattice constant of the photonic crystal.

4. The surface-emitting laser with high speed according to claim 3, characterized in that The nanopores are circular, triangular or square. When the nanopores are circular or triangular, the number of nanopores in each unit cell is six, and the corresponding unit cell is a regular hexagon; when the nanopores are square, the number of nanopores in each unit cell is four, and the corresponding unit cell is a square.

5. The surface-emitting laser according to claim 3, characterized in that, A dielectric material with a refractive index less than that of the surrounding medium is filled in the nanopores.

6. The high-speed surface-emitting laser according to claim 3, characterized in that, Both the N-type contact layer and the P-type contact layer are doped layers, and the doping concentration of the doped layer exceeds 5×10 18 cm -3 .

7. A method for preparing a high-speed surface-emitting laser according to any one of claims 1 to 6, characterized in that, Including the following steps: S1. An N-type contact layer, an N-type confinement layer, an active layer, a P-type confinement layer and a P-type contact layer are sequentially grown on an N-type substrate. S2. Etch downward from the P-type contact layer to the P-type confinement layer to form a topologically non-trivial state photonic crystal and a topologically trivial state photonic crystal; wherein, the topologically non-trivial state photonic crystal is surrounded by the topologically trivial state photonic crystal to form two resonant cavities and a coupling channel for coupling the two resonant cavities, and a high-resistance region is realized at the coupling channel by means of proton implantation. S3. At a position avoiding the topologically non-trivial state photonic crystal and the topologically trivial state photonic crystal, etch downward from the P-type contact layer to the N-type contact layer to form a mesa. S4. Deposit an electrode material on the P-type contact layer on the mesa to form a P-side electrode, and deposit an electrode material on the N-type contact layer outside the mesa to form an N-side electrode. S5. Deposit a planarization material layer at a position outside the mesa avoiding the N-side electrode, which is at the same height as the P-side electrode. S6. Use the planarization material layer to lead out the P-side electrode and the N-side electrode to the same height to form a coplanar electrode.

8. The manufacturing method of the high-speed surface-emitting laser according to claim 7, characterized in that, In step S1, an oxidizable layer is prepared between the active layer and the N-type confinement layer and / or between the active layer and the P-type confinement layer. The oxidizable layer forms an insulating material by oxidizing the edge portion, and the unoxidized portion at the center forms an aperture for current to flow through.

9. A method for preparing a high-speed surface-emitting laser according to any one of claims 1 to 6, characterized in that, Including the following steps: S1. An N-type contact layer, an N-type confinement layer, an active layer and a P-type confinement layer are sequentially grown on an N-type substrate. S2. Etch downward in the P-type confinement layer to a position close to the active layer to form a topologically non-trivial state photonic crystal and a topologically trivial state photonic crystal; wherein, the topologically non-trivial state photonic crystal is surrounded by the topologically trivial state photonic crystal to form two resonant cavities and a coupling channel for coupling the two resonant cavities, and a high-resistance region is realized at the coupling channel by means of proton implantation; S3. Grow a P-type contact layer on the P-type confinement layer; S4. Avoiding the topologically non-trivial state photonic crystal and the topologically trivial state photonic crystal, etch downward from the P-type contact layer to the N-type confinement layer to form a mesa; S5. Deposit a layer of electrode material on the P-type contact layer on the mesa to form a P-side electrode, and deposit a layer of electrode material on the N-type confinement layer outside the mesa to form an N-side electrode; S6. Deposit a planarization material layer with the same height as the P-side electrode at a position outside the mesa and avoiding the N-side electrode; S7. Use the planarization material layer to lead out the P-side electrode and the N-side electrode to the same height to form coplanar electrodes.

10. The manufacturing method of the high-speed surface-emitting laser according to claim 9, characterized in that, In step S1, an oxidizable layer is prepared between the active layer and the N-type confinement layer and / or between the active layer and the P-type confinement layer. The oxidizable layer forms an insulating material by oxidizing the edge part, and the unoxidized part in the center forms an aperture for current flow.

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