Active feedback laser and preparation method thereof

Abstract

The invention provides an active feedback laser and a preparation method, and relates to the technical field of semiconductor lasers. The active feedback laser comprises a first ridge waveguide used for generating a first light beam through injected first current; the at least one second ridge waveguide is electrically isolated from the first ridge waveguide and used for generating at least one second light beam, and one second ridge waveguide generates one second light beam through the injected second current; the at least one third ridge waveguide is in passive connection with the first ridge waveguide and the at least one second ridge waveguide and is used for coupling the at least one received second light beam into the first ridge waveguide; wherein in the first ridge waveguide, the received at least one second light beam and the first light beam form a photon-photon resonance effect.

Description

Technical Field

[0001] The present disclosure relates to the technical field of semiconductor lasers, and more specifically, to an active feedback laser and a preparation method thereof. Background Art

[0002] Distributed Feedback Bragg lasers (DFB) have attracted extensive attention from academia and industry due to their high electro-optical conversion efficiency, compact size, flexible structure and excellent reliability. Its advantages include single-mode operation, monolithic integration and low cost, which give it significant advantages in a variety of applications. The working principle of DFB lasers is based on a built-in distributed Bragg reflection grating, which is directly embedded in or close to the active area. It achieves stable single-mode output by selectively feeding back photons of a specific wavelength, and can further optimize the mode stability by introducing a λ / 4 phase shift. However, the current DFB laser has a small modulation bandwidth, which is not conducive to the application requirements of high-speed data transmission. Summary of the invention

[0003] In view of this, the present disclosure provides an active feedback laser and a preparation method thereof.

[0004] On the one hand, the present disclosure provides an active feedback laser, comprising: a first ridge waveguide, used to generate a first light beam by injecting a first current; at least one second ridge waveguide, electrically isolated from the first ridge waveguide, used to generate at least one second light beam, and a second ridge waveguide generates a second light beam by injecting a second current; at least one third ridge waveguide, passively connected to the first ridge waveguide and the at least one second ridge waveguide, used to couple the received at least one second light beam into the first ridge waveguide; wherein, in the first ridge waveguide, the received at least one second light beam forms a photon-photon resonance effect with the first light beam.

[0005] According to an embodiment of the present disclosure, generating at least one second light beam includes: controlling the timing of the corresponding at least one second light beam by regulating the magnitude of the second current injected into the at least one second ridge waveguide.

[0006] According to an embodiment of the present disclosure, at least one third ridge waveguide is further used to regulate the first phase of at least one received second light beam so that the first phase matches the second phase of the first light beam.

[0007] According to an embodiment of the present disclosure, regulating the first phase of at least one second light beam received includes: injecting a third current into at least one third ridge waveguide, and controlling the first phase of at least one second light beam by controlling the magnitude of the third current.

[0008] According to an embodiment of the present disclosure, the active feedback laser further includes: an N-type electrode coplanar with the first ridge waveguide, the at least one second ridge waveguide, and the at least one third ridge waveguide.

[0009] A second aspect of the present disclosure provides an active feedback laser, comprising: a first ridge waveguide, used to generate a first light beam by injecting a first current; and at least one second ridge waveguide, passively connected to the first ridge waveguide, used to generate at least one second light beam, and couple the at least one second light beam into the first ridge waveguide so that the at least one second light beam forms a photon-photon resonance effect with the first light beam; wherein a second ridge waveguide generates a second light beam by injecting a second current.

[0010] According to an embodiment of the present disclosure, the timing of the corresponding at least one second light beam is controlled by regulating the magnitude of the second current injected into the at least one second ridge waveguide.

[0011] According to an embodiment of the present disclosure, the active feedback laser further includes: an N-type electrode coplanar with the first ridge waveguide and the at least one second ridge waveguide.

[0012] According to an embodiment of the present disclosure, the active feedback laser further includes: a grating structure disposed on both sides of the first ridge waveguide.

[0013] The third aspect of the present disclosure provides a method for preparing an active feedback laser, comprising: preparing a growth structure by epitaxial growth on a substrate; etching a first ridge waveguide, at least one second ridge waveguide, and at least one third ridge waveguide on the growth structure; wherein the first ridge waveguide is used to generate a first light beam by injecting a first current; at least one second ridge waveguide is electrically isolated from the first ridge waveguide and is used to generate at least one second light beam, and a second ridge waveguide generates a second light beam by injecting a second current; at least one third ridge waveguide is passively connected to the first ridge waveguide and the at least one second ridge waveguide and is used to couple the received at least one second light beam into the first ridge waveguide; in the first ridge waveguide, the received at least one second light beam forms a photon-photon resonance effect with the first light beam;

[0014] Or: etching a first ridge waveguide and at least one second ridge waveguide on the growth structure; wherein the first ridge waveguide is used to generate a first light beam by injecting a first current; and at least one second ridge waveguide is passively connected to the first ridge waveguide, used to generate at least one second light beam, and couple the at least one second light beam into the first ridge waveguide so that the at least one second light beam forms a photon-photon resonance effect with the first light beam; a second ridge waveguide generates a second light beam by injecting a second current.

[0015] The active feedback laser provided in the embodiments of the present disclosure has at least the following beneficial effects:

[0016] By injecting current into at least one second ridge waveguide to generate at least one second light beam, independent control and flexible adjustment of the second ridge waveguide light source are achieved. At the same time, complex transmission paths are avoided, signal loss and the possibility of noise introduction due to transmission are reduced, which is conducive to achieving a higher modulation bandwidth.

[0017] In the case where the first ridge waveguide and the second ridge waveguide are electrically isolated, at least one third ridge waveguide is provided to couple the generated second light beam into the first ridge waveguide by means of passive connection, thereby avoiding the complex active modulation process and reducing the loss and noise in the signal transmission path. And by precisely controlling the current injection of the second ridge waveguide and the third ridge waveguide, the second light beam can be coupled into the first ridge waveguide at a specific time point and phase, thereby effectively improving the modulation bandwidth and high-speed performance.

[0018] The first ridge waveguide and the second ridge waveguide are directly and passively connected to directly generate and couple the second light beam to the first ridge waveguide, which simplifies the complexity of the system, shortens the transmission path, reduces feedback delay, and helps to improve the response speed and high-speed characteristics of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0020] Figure 1 A schematic diagram of an active feedback laser according to an embodiment of the present disclosure is schematically shown;

[0021] Figure 2 Schematically shows an AA side view according to an embodiment of the present disclosure;

[0022] Figure 3 Schematically shows a schematic diagram of an active feedback laser according to another embodiment of the present disclosure;

[0023] Figure 4 Schematically shows an AA side view according to another embodiment of the present disclosure;

[0024] Figure 5 The preparation method according to one embodiment of the present disclosure is schematically shown. DETAILED DESCRIPTION

[0025] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known systems and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0026] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0027] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0028] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0029] DFB lasers use grating mirrors, and the gratings contain gain. According to the position of the grating in the device structure, O-wave direct-modulated DFB lasers are mainly divided into two types: tunnel buried structure (Buried Waveguide DFB, referred to as BW-DFB) and ridge waveguide grating structure (Ridge Waveguide Distributed Feedback Laser, referred to as RGW-DFB). Among them, the BW-DFB structure requires secondary epitaxial growth after grating etching, which will lead to many internal defects in the material. In addition, this structure usually uses Zn to diffuse from the current blocking layer to the active area, which can easily make the optical loss and parasitic capacitance in the pnp BH structure larger. Compared with the tunnel buried structure, RGW-DFB does not require secondary epitaxial growth, which reduces complex manufacturing steps, production costs and process difficulties. At the same time, since it does not require secondary epitaxial growth, it has fewer internal defects, lower parasitic capacitance and high stability, and is suitable for high-speed data transmission.

[0030] The present disclosure provides an active feedback laser, comprising:

[0031] The first ridge waveguide is used to generate a first light beam by injecting a first current.

[0032] At least one second ridge waveguide is electrically isolated from the first ridge waveguide and is used to generate at least one second light beam. A second ridge waveguide generates a second light beam by injecting a second current.

[0033] At least one third ridge waveguide is passively connected to the first ridge waveguide and the at least one second ridge waveguide through a passive waveguide, and is used to couple the received at least one second light beam into the first ridge waveguide.

[0034] Wherein, in the first ridge waveguide, the received at least one second light beam forms a photon-photon resonance effect (Photon-Photon Resonance, PPR for short) with the first light beam.

[0035] In the embodiments of the present disclosure, the first ridge waveguide serves as the main cavity, at least one second ridge waveguide serves as the feedback cavity, and at least one third ridge waveguide serves as the coupling cavity, all of which are arranged on the quantum well and quantum dot epitaxial structure. Feedback and coupling can be combined to achieve at least one second light beam coupled into the main cavity to form a PPR effect.

[0036] By introducing at least one second beam and forming a PPR effect with the first beam in the first ridge waveguide, a response peak can be added to the relaxation oscillation peak of the laser. This additional response peak helps to break through the relaxation bandwidth limitation of traditional quantum dot lasers, thereby increasing the overall modulation bandwidth and can be used in the O band.

[0037] Each second ridge waveguide generates a light beam by independently injecting a second current. This independent control can accurately adjust the output power, phase and other parameters of each feedback light source, avoiding unnecessary optical feedback and interference, thereby reducing optical losses. The second ridge waveguide is electrically isolated from the first ridge waveguide, which means that the electrical interaction between them is minimized, reducing additional noise and loss caused by electrical crosstalk.

[0038] The third ridge waveguide is passively connected to the first ridge waveguide and the second ridge waveguide. Passive connection means that no additional active components are required to guide the light beam, reducing the loss introduced by active components.

[0039] Therefore, the second light beam generated in this embodiment can be efficiently coupled into the first ridge waveguide, reducing optical loss, so that the second light beam forms a photon-photon resonance effect with the first light beam, and has high modulation bandwidth and high high-speed characteristics.

[0040] Figure 1 A schematic diagram of an active feedback laser according to an embodiment of the present disclosure is shown schematically.

[0041] Figure 2 The AA side view according to an embodiment of the present disclosure is schematically shown.

[0042] In some possible embodiments, the number of the at least one second ridge waveguide may be 2, and the number of the at least one third ridge waveguide may be 2, but is not limited thereto.

[0043] like Figure 1 As shown, the active feedback laser includes: the first ridge waveguide 1 generates a first light beam by injecting a first current. The second ridge waveguides 21 and 22 generate two second light beams by injecting a second current, and the first ridge waveguide 1 is isolated from the second ridge waveguides 21 and 22 by electrical isolation 41 and 42. The third ridge waveguides 31 and 32 are passively connected to the first ridge waveguide 1 and the second ridge waveguides 21 and 22 through passive waveguides.

[0044] Among them, the first ridge waveguide 1, the second ridge waveguides 21 and 22, and the third ridge waveguides 31 and 32 are all provided with corresponding GSG (Ground Signal Groun, ground-signal-ground) pins. In the embodiment of the present disclosure, by providing multiple second ridge waveguides, additional optical feedback paths can be provided at different positions, which can break through the modulation bandwidth limitation caused by a single feedback path, further improve the overall modulation bandwidth, and have higher high-speed characteristics.

[0045] In the embodiment of the present disclosure, the active feedback laser further includes an N-type electrode 5 .

[0046] Based on the above embodiment, generating at least one second light beam includes: controlling the timing of the corresponding at least one second light beam by regulating the magnitude of the second current injected into the at least one second ridge waveguide.

[0047] In an embodiment of the present disclosure, the photon-photon resonance effect relies on the interaction between photons of different frequencies. By precisely controlling the timing of the second light beam, the time when these light beams arrive at the first ridge waveguide can be adjusted, thereby more effectively achieving resonance between photons. And each second ridge waveguide has an independent current injection path, allowing the intensity of each second light beam to be adjusted individually. By changing the magnitude of the second current, the output power of each second light beam can be controlled. By precisely controlling the magnitude of the injected current, it is ensured that the second light beam enters the first ridge waveguide at the desired timing. When the second light beam is coupled into the first ridge waveguide, it interacts with the first light beam to form a PPR. By precisely controlling the timing of the second light beam, the resonance effect can be optimized, thereby increasing the oscillation frequency and stability of the first ridge waveguide, thereby improving the high-speed characteristics of the laser.

[0048] On the basis of the above embodiment, at least one third ridge waveguide is further used to: regulate the first phase of at least one second light beam received by controlling the magnitude of the injected third current so that the first phase matches the second phase of the first light beam. This allows the at least one second light beam to be efficiently coupled to the first ridge waveguide. This can optimize the coupling effect of the second light beam from the second ridge waveguide to the first ridge waveguide and reduce optical loss.

[0049] On the basis of the above embodiment, the active feedback laser further includes: an N-type electrode 5 coplanar with the first ridge waveguide, at least one second ridge waveguide and at least one third ridge waveguide.

[0050] In the embodiments of the present disclosure, a coplanar electrode structure is used to reduce the current transmission path, reduce the influence of parasitic resistance and parasitic capacitance, and increase bandwidth.

[0051] On the basis of the above embodiment, the active feedback laser further includes: a grating structure 6, which is arranged on both sides of the first ridge waveguide and both sides of at least one third ridge waveguide, and is used for selective feedback to achieve single-mode emission of the laser.

[0052] Figure 3 A schematic diagram of an active feedback laser according to another embodiment of the present disclosure is schematically shown.

[0053] Figure 4 The AA side view according to another embodiment of the present disclosure is schematically shown.

[0054] like Figure 3 and Figure 4 As shown, the present disclosure provides an active feedback laser, comprising:

[0055] The first ridge waveguide 1 is used to generate a first light beam by injecting a first current.

[0056] At least one second ridge waveguide is passively connected to the first ridge waveguide through the passive waveguide 7. It is used to generate at least one second light beam and couple the at least one second light beam into the first ridge waveguide so that the at least one second light beam forms a photon-photon resonance effect with the first light beam.

[0057] A second ridge waveguide generates a second light beam by injecting a second current.

[0058] In the embodiments of the present disclosure, the first ridge waveguide serves as the main cavity, and at least one second ridge waveguide serves as the feedback cavity. The main cavity and the feedback cavity are directly and passively connected, and both are arranged on the quantum well and quantum dot epitaxial structure, so that at least one second light beam can be coupled into the main cavity to form a PPR effect.

[0059] The second ridge waveguide generates a second light beam as an auxiliary light source by directly controlling the magnitude of the injected second current. The second ridge waveguide and the first ridge waveguide are passively connected to directly couple the generated second light beam into the first ridge waveguide, thereby avoiding optical loss caused by active modulation, simplifying the structure, and shortening the transmission path of the light beam. At the same time, the second light beam is generated by independently regulating the injected second current, thereby improving the flexibility of adjustment.

[0060] For example, the number of at least one second ridge waveguide can be selected and set as needed, such as Figure 3 As shown, there may be two second ridge waveguides, namely 21 and 22 .

[0061] The active feedback laser includes: a first ridge waveguide 1 generates a first light beam by injecting a first current, and second ridge waveguides 21 and 22 generate two second light beams by injecting a second current, and the first ridge waveguide 1 is passively connected to the second ridge waveguides 21 and 22 by a passive waveguide 7, and is arranged on an epitaxial wafer.

[0062] The first ridge waveguide 1 and the second ridge waveguides 21 and 22 are both provided with corresponding GSG (Ground Signal Groun, ground-signal-ground) pins and are connected through electrode leads. In the embodiment of the present disclosure, by providing multiple second ridge waveguides, additional optical feedback paths can be provided at different positions, which can break through the modulation bandwidth limitation caused by a single feedback path, further improve the overall modulation bandwidth, and have higher high-speed characteristics.

[0063] According to an embodiment of the present disclosure, the timing of the corresponding at least one second light beam is controlled by regulating the magnitude of the second current injected into the at least one second ridge waveguide.

[0064] In the embodiments of the present disclosure, the magnitude of the second current is independently controlled, thereby controlling the timing of coupling the second light beam to the first ridge waveguide to achieve the maximum oscillation frequency of the main cavity, thereby improving the high-speed characteristics of the device.

[0065] In this embodiment, the active feedback laser further includes: an N-type electrode 5, which is coplanar with the first ridge waveguide and at least one second ridge waveguide, and can effectively reduce the propagation path of the current.

[0066] According to an embodiment of the present disclosure, the active feedback laser further includes: a grating structure disposed on both sides of the first ridge waveguide.

[0067] A third aspect of the present disclosure provides a method for preparing an active feedback laser, comprising:

[0068] Step 1: Prepare a growth structure by epitaxial growth on a substrate.

[0069] Step 2: Etching a first ridge waveguide, at least one second ridge waveguide and at least one third ridge waveguide on the growth structure.

[0070] The first ridge waveguide is used to generate a first light beam by injecting a first current.

[0071] And at least one second ridge waveguide, electrically isolated from the first ridge waveguide, for generating at least one second light beam, wherein the second ridge waveguide generates a second light beam by injecting a second current.

[0072] At least one third ridge waveguide is passively connected to the first ridge waveguide and the at least one second ridge waveguide, and is used to couple the received at least one second light beam into the first ridge waveguide.

[0073] In the first ridge waveguide, the received at least one second light beam forms a photon-photon resonance effect with the first light beam.

[0074] or:

[0075] A first ridge waveguide and at least one second ridge waveguide are etched on the growth structure.

[0076] The first ridge waveguide is used to generate a first light beam by injecting a first current.

[0077] and at least one second ridge waveguide, passively connected to the first ridge waveguide, for generating at least one second light beam and coupling the at least one second light beam into the first ridge waveguide so that the at least one second light beam forms a photon-photon resonance effect with the first light beam. A second ridge waveguide generates a second light beam by injecting a second current.

[0078] In the embodiments of the present disclosure, the above-mentioned device can be prepared by a single epitaxial growth, which effectively reduces the internal defects of the material. At the same time, the preparation method is simple and the modulation bandwidth is effectively improved.

[0079] Figure 5 The preparation method of the embodiment of the present disclosure is schematically shown.

[0080] by Figure 1 Take the active feedback laser as an example, Figure 5 As shown, the present disclosure provides a method for preparing an active feedback laser, comprising:

[0081] Step 1: If Figure 5 As shown in (1), an epitaxial growth is carried out on the substrate to form a multi-layer growth structure.

[0082] Step 2: As shown in (2), a layer of metal is plated on the growth structure, as shown in (3)-(5), and a photoresist is coated and photolithography and etching are performed to prepare the ridge waveguide and the electrode, and then the excess photoresist is removed;

[0083] Step 3: As shown in (6)-(8), apply photoresist, etch the grating structure on both sides of the first ridge waveguide and the two third ridge waveguides, and then remove the excess photoresist.

[0084] Step 4: As shown in (9)-(11), apply photoresist, etch the N-type electrode area, and then remove excess photoresist.

[0085] Step 5: As shown in (12)-(16), apply photoresist, after exposure, evaporate P-type electrode, remove the resist, and bond the wires.

[0086] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0087] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. An active feedback laser, characterized in that: include: a first ridge waveguide for generating a first light beam by injecting a first current; At least one second ridge waveguide, electrically isolated from the first ridge waveguide, for generating at least one second light beam, wherein the second ridge waveguide generates a second light beam by injecting a second current; at least one third ridge waveguide, passively connected to the first ridge waveguide and the at least one second ridge waveguide, for coupling the received at least one second light beam into the first ridge waveguide; Wherein, in the first ridge waveguide, the at least one second light beam received forms a photon-photon resonance effect with the first light beam.

2. The active feedback laser according to claim 1, characterized in that: Generating at least one second light beam comprises: The timing of the corresponding at least one second light beam is controlled by adjusting the magnitude of the second current injected into the at least one second ridge waveguide.

3. The active feedback laser according to claim 1, characterized in that: The at least one third ridge waveguide is further used to adjust a first phase of the at least one second light beam received so that the first phase matches a second phase of the first light beam.

4. The active feedback laser according to claim 1, characterized in that: The adjusting the first phase of the at least one second light beam received comprises: A third current is injected into the at least one third ridge waveguide, and the first phase of the at least one second light beam is controlled by controlling the magnitude of the third current.

5. The active feedback laser according to claim 1, characterized in that: Also includes: The N-type electrode is coplanar with the first ridge waveguide, the at least one second ridge waveguide and the at least one third ridge waveguide.

6. An active feedback laser, characterized in that: include: a first ridge waveguide for generating a first light beam by injecting a first current; as well as At least one second ridge waveguide is passively connected to the first ridge waveguide, and is used to generate at least one second light beam, and couple the at least one second light beam into the first ridge waveguide so that the at least one second light beam forms a photon-photon resonance effect with the first light beam; wherein a second ridge waveguide generates a second light beam by injecting a second current.

7. The active feedback laser according to claim 6, characterized in that: Generating at least one second light beam comprises: The timing of the corresponding at least one second light beam is controlled by adjusting the magnitude of the second current injected into the at least one second ridge waveguide.

8. The active feedback laser according to claim 6, characterized in that: Also includes: An N-type electrode is coplanar with the first ridge waveguide and the at least one second ridge waveguide.

9. The active feedback laser according to claim 6, characterized in that: Also includes: The grating structure is arranged on both sides of the first ridge waveguide.

10. A method for preparing an active feedback laser, characterized in that: include: epitaxially growing a growth structure on a substrate; Etching a first ridge waveguide, at least one second ridge waveguide and at least one third ridge waveguide on the growth structure; Wherein, the first ridge waveguide is used to generate a first light beam by injecting a first current; The at least one second ridge waveguide is electrically isolated from the first ridge waveguide and is used to generate at least one second light beam, wherein the second ridge waveguide generates a second light beam by injecting a second current; The at least one third ridge waveguide is passively connected to the first ridge waveguide and the at least one second ridge waveguide, and is used to couple the received at least one second light beam into the first ridge waveguide; In the first ridge waveguide, the received at least one second light beam forms a photon-photon resonance effect with the first light beam; or: etching a first ridge waveguide and at least one second ridge waveguide on the growth structure; Wherein, the first ridge waveguide is used to generate a first light beam by injecting a first current; and The at least one second ridge waveguide is passively connected to the first ridge waveguide, and is used to generate at least one second light beam, and couple the at least one second light beam into the first ridge waveguide so that the at least one second light beam forms a photon-photon resonance effect with the first light beam; a second ridge waveguide generates a second light beam by injecting a second current.

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