CN114583541A - Hybrid integrated laser - Google Patents

Abstract

The invention discloses a hybrid integrated laser, comprising: an optical gain region, a first optical reflector, a second optical reflector, and a phase region; the optical gain area is arranged on the first chip and comprises a semiconductor optical amplifying element; the first optical reflector is integrated on the second chip, the second optical reflector is integrated on the first chip or the second chip, and the first optical reflector, the second optical reflector and an optical waveguide loop between the first optical reflector and the second optical reflector form an optical resonant cavity of the hybrid integrated laser; the optical gain area and the phase area are both positioned in the optical resonant cavity; the second light reflector comprises a Sagnac reflector or a reflective end facet disposed on a waveguide in the semiconductor optical amplifying element; therefore, the narrow-linewidth semiconductor laser is realized, the narrow-linewidth semiconductor laser is ensured to have lower process difficulty and manufacturing cost, high-speed modulation with large bandwidth and adjustable chirp of the laser can be further realized on the basis, and the application requirement of medium-distance and long-distance optical communication is met.

Description

Hybrid Integrated Laser

technical field

The present invention relates to the technical field of lasers, in particular to a hybrid integrated laser.

Background technique

Existing semiconductor lasers mainly include DFB laser (Distributed Feedback Laser, distributed feedback laser), DBR (Distributed Bragg Reflector, distributed Bragg reflector) laser and EML (Electro-absorption Modulated Laser, electro-absorption modulated laser). The first two can be used as continuous wave lasers or as electro-optical intensity-modulated lasers, while EML is a monolithic integration of DFB lasers and EAM (ElectroAbsorption Modulator, electro-absorption modulator).

DFB lasers are widely used in the fields of optical communication and optical sensing due to the small size and low cost of the Bragg gratings used for filtering mode selection in the active gain region. However, its disadvantage is that the bandwidth of electro-optical modulation is low due to the influence of relaxation oscillation, and the modulation chirp is relatively large, which is not suitable for broadband and long-distance transmission applications.

DBR lasers place the Bragg grating used for filtering mode selection outside the active gain region, which can realize narrow-band filtering, but in addition to the narrower laser linewidth than DFB lasers, there is no modulation bandwidth and modulation chirp. However, its size is larger than that of DFB lasers, so most of them are used as continuous wave lasers and are less used. The main application of DBR lasers is to use the Vernier effect to construct wavelength-tunable lasers, but most of the existing technologies are based on the monolithic integration of active region gain region materials. Although the integration is high, the process is difficult to achieve and the cost is high.

EML uses DFB lasers as continuous wave lasers and uses electro-absorption modulators to achieve light intensity modulation, which has improved in modulation bandwidth and chirp, but it is still difficult in large-bandwidth, long-distance transmission applications.

SUMMARY OF THE INVENTION

The present invention provides a hybrid integrated laser, so as to realize a narrow line width semiconductor laser while ensuring that the narrow line width semiconductor laser has lower process difficulty and manufacturing cost, and on this basis, further realize the narrow line width The high-speed modulation of semiconductor lasers with large bandwidth and adjustable chirp can meet the application requirements of medium and long-distance optical communication.

In a first aspect, an embodiment of the present invention provides a hybrid integrated laser, including: an optical gain region, a first optical reflector, a second optical reflector, and a phase region, the first optical reflector including a DBR reflector;

The optical gain area is arranged on the first chip, and the optical gain area includes a semiconductor optical amplifying element; the first light reflector is integrated on the second chip, and the second light reflector is integrated on the first chip On the chip or the second chip, the first optical reflector, the second optical reflector and the optical waveguide loop between them constitute an optical resonant cavity of the hybrid integrated laser;

Both the semiconductor optical amplifying element and the phase region are located in the optical resonant cavity; the phase region is integrated on the first chip or the second chip, and the phase region is used to control the optical In the resonant cavity, the light wavelength of the spectral passband after the cascade connection of the first light reflector and the second light reflector satisfies the resonance condition;

Wherein, the second light reflector includes a Sagnac reflector or a reflective end face disposed on a waveguide in the semiconductor optical amplifying element.

Optionally, the semiconductor optical amplifying element includes a straight waveguide and a first semiconductor optical amplifier;

The second light reflector includes the reflective end face, the reflective end face is arranged on the first port of the straight waveguide, and the second port of the straight waveguide is positioned on the end face of the first chip for light transmission end; the first end of the DBR reflector is optically coupled with the optical transmission end, and a part of the laser light in the optical resonator is output through the second end of the DBR reflector;

The straight waveguide is a straight active waveguide and the straight active waveguide is a waveguide inside the first semiconductor optical amplifier; or, the straight waveguide is a straight passive waveguide and the first semiconductor optical amplifier The inner waveguide is a straight waveguide or a curved waveguide.

Optionally, the core layer material of the optical transmission waveguide of the second chip is thin-film lithium niobate, and a Mach-Zehnder modulator is also integrated on the second chip;

The first end of the Mach-Zehnder modulator is connected with the second end of the first optical reflector through an optical transmission waveguide in the second chip, and the second end of the Mach-Zehnder modulator outputs an output The laser light output by the second end of the first light reflector.

Optionally, the semiconductor optical amplifying element includes a U-shaped waveguide and a first semiconductor optical amplifier; two ports of the U-shaped waveguide are respectively connected to corresponding straight waveguides in the first chip, and are connected to the U-shaped waveguide. The two sections of the straight waveguide corresponding to the two ports of the waveguide are respectively extended to the same end face of the first chip, thereby forming a first optical transmission end and a second optical transmission end on the end face of the first chip;

The second light reflector includes a Sagnac reflector; the first end of the Sagnac reflector is optically coupled to the first optical transmission end, and the first end of the DBR reflector is optically coupled to the second optical transmission end. Coupling, a part of the laser light in the optical resonator is output through the second end of the Sagnac reflector or the second end of the DBR reflector;

the U-shaped waveguide is a U-shaped active waveguide and the U-shaped active waveguide is a waveguide inside the first semiconductor optical amplifier;

Alternatively, the U-shaped waveguide is a U-shaped passive waveguide and the waveguide inside the first semiconductor optical amplifier is a straight waveguide or a curved waveguide.

Optionally, the core layer material of the optical transmission waveguide of the second chip is thin-film lithium niobate, and a Mach-Zehnder modulator is also integrated on the second chip;

The first end of the Mach-Zehnder modulator is connected to the second end of the Sagnac reflector through an optical transmission waveguide in the second chip, and the output of the second end of the Mach-Zehnder modulator is provided by the laser output from the second end of the Sagnac reflector.

Optionally, the hybrid integrated laser further includes: a second semiconductor optical amplifier;

The second semiconductor optical amplifier is used for amplifying and outputting the laser light output by the second end of the Mach-Zehnder modulator.

Optionally, an anti-reflection film is provided on at least one of the end faces where the first chip and the second chip are optically coupled.

Optionally, the hybrid integrated laser further includes: a microlens; the first chip and the second chip are optically coupled through the microlens, and/or the laser output end face of the hybrid integrated laser is connected to the external The optical fibers are optically coupled through the microlenses.

Optionally, the hybrid integrated laser further includes: an optical isolator; the optical isolator is arranged between the laser output end face of the hybrid integrated laser and an external optical fiber.

In a second aspect, an embodiment of the present invention further provides a multi-channel hybrid integrated laser, including a plurality of hybrid integrated lasers as described in the first aspect;

The plurality of hybrid integrated lasers share the same first chip and share the same second chip.

The hybrid integrated laser provided by the embodiment of the present invention includes an optical gain area, a first optical reflector, a second optical reflector and a phase area; the optical gain area is arranged on the first chip, and the optical gain area includes a semiconductor optical amplifier element.

By setting the first optical reflector to include a DBR reflector, the laser output laser linewidth is narrow to meet the narrow linewidth requirements of the coherent optical communication system for the laser, and at the same time, by setting the second optical reflector to include a Sagnac reflector or a The reflective end face on the waveguide in the semiconductor optical amplifier element, the first optical reflector, the second optical reflector and the optical waveguide loop between them constitute the optical resonator of the hybrid integrated laser, and the optical gain region and phase region are located in the optical In the resonant cavity, and the first light reflector is integrated on the second chip, and the second light reflector is integrated on the first or second chip, so that the narrow linewidth semiconductor laser is realized, and the hybrid integration between chips is achieved. It is ensured that the narrow linewidth semiconductor laser has lower technological difficulty and manufacturing cost.

Moreover, the optical gain region and the first light reflector are respectively integrated on the first chip and the second chip, and the materials of the first chip and the second chip may be different. In the case of setting the second chip to use a thin-film lithium niobate wafer, the high-speed electro-optic modulator can be further integrated into the second chip, thereby realizing a high-speed modulated hybrid integrated laser, greatly improving the bandwidth and transmission distance, That is to achieve high-speed modulation of narrow linewidth semiconductor laser with large bandwidth and adjustable chirp, and meet the application requirements of medium and long-distance optical communication.

It should be understood that the content described in this section is not intended to identify key or critical features of the embodiments of the invention, nor is it intended to limit the scope of the invention. Other features of the present invention will become readily understood from the following description.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a schematic top-view structural diagram of a hybrid integrated laser provided by an embodiment of the present invention;

2 is a light reflection spectrum diagram of a hybrid integrated laser provided by an embodiment of the present invention;

3 is a schematic top-view structural diagram of another hybrid integrated laser provided by an embodiment of the present invention;

4 is a schematic top-view structural diagram of another hybrid integrated laser provided by an embodiment of the present invention;

5 is a schematic top-view structural diagram of another hybrid integrated laser provided by an embodiment of the present invention;

6 is a schematic top-view structure diagram of another hybrid integrated laser provided by an embodiment of the present invention;

FIG. 7 is a schematic top-view structural diagram of a multi-channel hybrid integrated laser according to an embodiment of the present invention.

Detailed ways

In order to make those skilled in the art better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only Embodiments are part of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that the terms "first", "second" and the like in the description and claims of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used may be interchanged under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having" and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those expressly listed Rather, those steps or units may include other steps or units not expressly listed or inherent to these processes, methods, products or devices.

FIG. 1 is a schematic top-view structural diagram of a hybrid integrated laser provided by an embodiment of the present invention. Referring to FIG. 1 , the hybrid integrated laser 10 includes: an optical gain area, a first optical reflector, a second optical reflector and a phase area 122 , the first optical reflector includes a DBR reflector 121 ; the optical gain area is provided on the first chip 11 , the optical gain region includes semiconductor optical amplification elements; the first light reflector is integrated on the second chip 12, the second light reflector is integrated on the first chip 11 or the second chip 12, the first light reflector, the second light reflector The optical reflector and the optical waveguide circuit between the two constitute the optical resonator of the hybrid integrated laser 10; the semiconductor optical amplification element and the phase region 122 are both located in the optical resonator, and the phase region 122 is integrated in the first chip 11 or the second chip 12, the phase region 122 is used to control the optical wavelength of the spectral passband after the cascade of the first optical reflector and the second optical reflector in the optical resonator to satisfy the resonance condition; wherein, the second optical reflector comprises a Sagnac reflector or The reflection end face 1111 provided on the waveguide in the semiconductor optical amplification element.

Specifically, the optical gain region is used to realize the optical gain function. The semiconductor optical amplifying element includes two parts: a semiconductor optical amplifier and a waveguide. The first optical reflector, the second optical reflector and the optical waveguide loop between them constitute the optical resonant cavity of the hybrid integrated laser 10 , and the optical waveguide loop may include the light in the first chip 11 and/or the second chip 12 The transmission waveguide, the semiconductor optical amplifying element and the phase region 122 are all located in the optical resonator, and the phase region 122 is used to adjust the phase of the light in the optical resonator, that is, the phase of the light round trip in the optical resonator is an integer multiple of 2π. The light in the optical resonator passes through the optical gain region and the phase region 122 and oscillates back and forth between the first light reflector and the second light reflector.

In the embodiment of the present invention, by setting the first optical reflector to include a DBR reflector 121, the DBR reflector 121 is used as a narrow-band filter, so as to realize the function of mode selection and output from multiple longitudinal modes that satisfy the resonance condition in the optical resonant cavity, so that the laser 10 outputs the output The laser linewidth is relatively narrow to meet the narrow linewidth requirements of the coherent optical communication system for the laser 10; FIG. 2 is a light reflection spectrum diagram of a hybrid integrated laser 10 provided by an embodiment of the present invention, the horizontal axis is the light wavelength λ, and the vertical axis is λ. The axis is the reflectance dB. As exemplarily shown in FIG. 2 , the light reflection spectrum includes the passband center wavelength λc, and the DBR reflector 121 partially reflects and partially transmits at the passband center wavelength λc as the laser output. On this basis, by setting the optical gain region on the first chip 11, the first light reflector is integrated on the second chip 12, and the second light reflector is integrated on the first chip 11 or the second chip 12, so as to The hybrid integrated DBR laser 10 is realized, so that the narrow linewidth semiconductor laser 10 has lower process difficulty and manufacturing cost by means of inter-chip hybrid integration while realizing the narrow linewidth semiconductor laser 10 .

In addition, the phase region 122 is exemplarily and schematically integrated on the second chip 12 in FIG. 1 , and the laser output of the hybrid integrated laser 10 can be realized by the first optical reflector or the second optical reflector.

The above are the main inventive concepts of the embodiments of the present invention. Based on the above technical solutions, the hybrid integrated laser 10 is quantified in two cases where the second optical reflector includes a Sagnac reflector or a reflective end face disposed on the waveguide in the semiconductor optical amplifying element. Explain in detail.

Optionally, continue to refer to FIG. 1 , in an embodiment of the present invention, the semiconductor optical amplification element is a semiconductor optical amplifier 111 with a straight waveguide, which includes a straight waveguide and a first semiconductor optical amplifier, and the straight waveguide includes two There are two opposite ports, namely the first port and the second port. The first port is provided with a reflective end surface 1111 , and the second port is located on the end surface of the first chip 11 and serves as the optical transmission end a, the optical transmission end a and the DBR reflector. The first end of the 121 is optically coupled, so that a part of the laser light in the optical resonator is output through the second end of the DBR reflector 121 as the laser output of the laser 10; wherein, the first end and the second end of the DBR reflector 121 In contrast, the optical properties of the first end and the second end are the same, and can be both reflective and transmissive.

Specifically, the DBR reflector 121 , the reflection end face 1111 and the optical waveguide loop between them constitute the optical resonant cavity of the hybrid integrated laser 10 . The reflection end surface 1111 is a high reflection surface. The reflective end face 1111 can be directly formed by the end face of the first port. In this case, the reflectivity of the end face of the first port can be set to be greater than the reflectivity of the end face of the second port, that is, the end face of the first port is a high reflection face, and the end face of the second port is low The first port end face is a high reflection surface, which can be realized by coating the first port end face with a high reflection film, and the second port end face is a low reflection surface, which can be realized by coating the second port end face with a low reflection film. Coating high and low reflection films is an optional solution, because even if the first and second ports are not coated, the reflectivity of the crystal end face itself can cooperate with the first light reflector to form an optical resonant cavity. The coating only makes the output of the laser 10 . more optical power. In FIG. 1 , the reflective end face 1111 is exemplarily shown on the end face of the first chip 11 away from the second chip 12 , because the port of the straight waveguide in the semiconductor optical amplification element can directly extend to the end face of the first chip 11 It extends to the end face of the first chip 11 on or through the light transmission waveguide in the first chip 11 .

In the embodiment of the present invention, the optical gain region and the light reflector are respectively integrated on the first chip 11 and the second chip 12 , so that the materials of the first chip 11 and the second chip 12 can be set to be different. In the embodiment of the present invention, the core layer material of the optical transmission waveguide in the second chip 12 may be thin-film lithium niobate (LiNbO ₃ ), silicon (Si), silicon nitride (Si ₃ N ₄ ), or silicon dioxide (SiO 3 ) ₂ ).

On the basis of the above-mentioned embodiments, optionally, FIG. 3 is a schematic top-view structural diagram of another hybrid integrated laser provided by an embodiment of the present invention. Referring to FIG. 3 , the core of the optical transmission waveguide in the second chip 12 is In the case where the layer material is thin-film lithium niobate, based on the high-speed electro-optic effect of the lithium niobate waveguide material, a Mach-Zehnder modulator 124 (Mach-Zehnder modulator) is further integrated on the second chip 12 , that is, the second chip 12 The DBR reflector 121 and the Mach-Zehnder modulator 124 are integrated in a parallel stage, so as to realize a hybrid integrated laser 10 that can be modulated at a high speed, and greatly improve the bandwidth and transmission distance, that is, to achieve a narrow linewidth semiconductor laser 10. Large bandwidth, chirp Adjustable high-speed modulation, and meet the application requirements of medium and long distance optical communication.

The first end of the Mach-Zehnder modulator 124 is connected to the second end of the first optical reflector through the optical transmission waveguide in the second chip 12, and the output of the second end of the Mach-Zehnder modulator 124 is transmitted by the first The laser output from the second end of the optical reflector is used as the output laser of the laser 10; the Mach-Zehnder modulator 124 can adjust its chirp by adjusting the DC bias operating point and the radio frequency voltage of the phase-shift arm of the Mach-Zehnder interferometer The chirp can be used to compensate for fiber dispersion with appropriate chirp. Accordingly, compared with the DFB laser and the EML, the hybrid integrated laser 10 provided by the embodiment of the present invention can greatly improve the bandwidth and transmission distance.

Optionally, in an embodiment of the present invention, the straight waveguide is a straight active waveguide and the straight active waveguide is a waveguide inside the first semiconductor optical amplifier; or, the straight waveguide is a straight passive waveguide And the waveguide inside the first semiconductor optical amplifier is a straight waveguide or a curved waveguide.

Optionally, FIG. 4 is a schematic top-view structure diagram of another hybrid integrated laser provided by an embodiment of the present invention. Referring to FIG. 4 , in another embodiment of the present invention, the semiconductor optical amplifying element is a U-shaped waveguide. The semiconductor optical amplifier 112 includes a U-shaped waveguide and a first semiconductor optical amplifier. The two ports of the U-shaped waveguide are respectively connected with the corresponding optical transmission straight waveguides in the first chip 11, corresponding to the two ports of the U-shaped waveguide. The two optical transmission straight waveguides extend to the same end face of the first chip 11 respectively, so as to form the first optical transmission end a1 and the second optical transmission end a2 on the end face of the first chip 11; the second optical reflector includes Sagnac The reflector 125, the first end of the Sagnac reflector 125 is optically coupled with the first optical transmission end a1, the first end of the DBR reflector 121 is optically coupled with the second optical transmission end a2, and a part of the laser light in the optical resonator passes through the Sagnac The second end of the reflector 125 or the second end of the DBR reflector 121 is output as the laser output of the laser 10 .

Specifically, the first optical transmission end a1 is cascaded with the Sagnac reflector 125 , the second optical transmission end a2 is cascaded with the DBR reflector 121 , the DBR reflector 121 , the Sagnac reflector 125 and the optical waveguide loop between them constitute Optical resonator of the hybrid integrated laser 10 . Optionally, when the U-shaped waveguide is a U-shaped active waveguide, the U-shaped active waveguide is a waveguide inside the first semiconductor optical amplifier; when the U-shaped waveguide is a U-shaped passive waveguide, the waveguide inside the first semiconductor optical amplifier is: Straight or curved waveguides.

On the basis of the above-mentioned embodiments, optionally, FIG. 5 is a schematic top-view structure diagram of another hybrid integrated laser provided by an embodiment of the present invention. Referring to FIG. 5 , the core layer of the optical transmission waveguide in the second chip 12 When the material is thin-film lithium niobate, a Mach-Zehnder modulator 124 is further integrated on the second chip 12, thereby realizing a hybrid integrated laser 10 that can be modulated at high speed, greatly improving the bandwidth and transmission distance, that is, realizing a narrow line width The semiconductor laser has 10 high-speed modulation with large bandwidth and adjustable chirp, and meets the application requirements of medium and long-distance optical communication. Wherein, the first end of the Mach-Zehnder modulator 124 is connected to the second end of the Sagnac reflector 125 through the optical transmission waveguide in the second chip 12, and the second end of the Mach-Zehnder modulator 124 is output by the first light The laser output from the second end of the reflector is used as the laser output of the laser 10 . In addition, the reflectivity of the Sagnac reflector 125 can be designed to be a desired value by setting the coupling coefficient of the directional coupler; of course, the Sagnac reflector 125 can also be cascaded with the Mach-Zehnder modulator 124, in this case generally The Sagnac reflector 125 is designed to be highly reflective.

On the basis of the above embodiments, the hybrid integrated laser 10 further includes: a second semiconductor optical amplifier for amplifying and outputting the laser light output by the second end of the Mach-Zehnder modulator 124 , in order to improve the output power of the hybrid integrated laser 10, the following takes the hybrid integrated laser 10 shown in FIG. 5 as an example to illustrate the situation where the laser 10 also includes a second semiconductor optical amplifier:

Exemplarily, FIG. 6 is a schematic top-view structural diagram of another hybrid integrated laser provided by an embodiment of the present invention. Referring to FIG. 6 , the second semiconductor optical amplifier is a semiconductor optical amplifier 113 with a straight waveguide (and a semiconductor optical amplifier with a straight waveguide). The semiconductor optical amplifier 111 is the same device), the semiconductor optical amplifier 113 with a straight waveguide is integrated on the first chip 11, and the first end of the semiconductor optical amplifier 113 with a straight waveguide is connected to the first end of the Mach-Zehnder modulator 124. The two ends are connected, and the second end of the semiconductor optical amplifier 113 with a straight waveguide amplifies and outputs the laser light output by the second end of the Mach-Zehnder modulator 124, that is, a part of the laser light in the optical resonator is reflected through the Sagnac in turn The output power of the hybrid integrated laser 10 can be increased by the second end of the modulator 125 , the second end of the Mach-Zehnder modulator 124 and the second end of the semiconductor optical amplifier 113 with a straight waveguide.

On the basis of the above embodiments, optionally, an anti-reflection film 123 is provided on at least one of the end faces where the first chip 11 and the second chip 12 are optically coupled and the laser output end face of the laser 10 .

Specifically, the relationship between the optical gain area and the first chip 11 can be understood as the chip provided with the optical gain area is the first chip 11, the first light reflector, the second light reflector, the Mach-Zehnder modulator 124 and the first light reflector The relationship between the two chips 12 can be understood as the chip that integrates the first light reflector, the second light reflector and the Mach-Zehnder modulator 124 is the second chip 12, so the first chip 11 and the second chip 12 perform optical The coupling is essentially the optical coupling between the optical reflector and the optical transmission end on the opposite end faces of the first chip 11 and the second chip 12. Continuing to refer to FIG. 6, this embodiment sets at least one end face of the end faces for optical coupling. An anti-reflection film 123 is provided to ensure the light transmission efficiency between the light reflector and the light transmission end.

The laser output end face is the end face of the output laser of the hybrid integrated laser 10. Referring to the technical solutions in the above embodiments, for example, the laser output end face can be the second end of the DBR reflector 121, the second end of the Sagnac reflector 125, the Mach - The second end of the Zehnder modulator 124 or the second end of the semiconductor optical amplifier 113 with a straight waveguide, etc., the laser output end face is coated with an anti-reflection film 123 to ensure the laser output efficiency of the laser output end face.

On the basis of the above embodiments, as an embodiment of the present invention, optionally, the hybrid integrated laser 10 further includes: a microlens; the first chip 11 and the second chip 12 are optically coupled through a microlens, and /or, the laser output end face of the hybrid integrated laser 10 and the external optical fiber are optically coupled through a microlens. Specifically, the first chip 11 and the second chip 12 are optically coupled through a microlens to further improve the optical coupling efficiency between the optical reflector and the optical transmission end; the laser output end face of the hybrid integrated laser 10 and the external optical fiber are optically coupled Micro-lens optical coupling to further improve the light output efficiency of the laser output end face.

On the basis of the above embodiments, as an embodiment of the present invention, optionally, the hybrid integrated laser 10 further includes: an optical isolator, and the optical isolator is arranged between the laser output end face of the hybrid integrated laser 10 and the external optical fiber. In other words, an optical isolator is arranged between the laser output end face and the external optical fiber, so as to avoid the influence of the system echo on the hybrid integrated laser 10 .

An embodiment of the present invention further provides a multi-channel hybrid integrated laser, and FIG. 7 is a schematic top-view structural diagram of a multi-channel hybrid integrated laser provided by an embodiment of the present invention. Referring to FIG. 7 , the multi-channel hybrid integrated laser includes a plurality of hybrid integrated lasers 10 implemented in any of the above-mentioned embodiments (four hybrid integrated lasers 10 are exemplarily shown in FIG. 7 ), and the multiple hybrid integrated lasers 10 share the same first The chips 11 share the same second chip 12 .

Specifically, the optical gain regions of the multiple hybrid integrated lasers 10 are integrated on the same first chip 11 , and the first optical reflectors of the multiple hybrid integrated lasers 10 are integrated on the same second chip 12 , as shown in FIG. 7 Illustratively, the second optical reflectors of the plurality of hybrid integrated lasers 10 each include a reflection end surface 1111 . The multi-channel hybrid integrated laser can output multiple different optical wavelengths at the same time as required, and sharing the first chip 11 and the second chip 12 can improve the integration degree of the multi-channel hybrid integrated laser.

The above-mentioned specific embodiments do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may occur depending on design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A hybrid integrated laser, comprising: an optical gain section, a first optical reflector, a second optical reflector, and a phase section, the first optical reflector comprising a DBR reflector;

the optical gain region is arranged on the first chip and comprises a semiconductor optical amplifying element; the first optical reflector is integrated on a second chip, the second optical reflector is integrated on the first chip or the second chip, and the first optical reflector, the second optical reflector and an optical waveguide loop between the first optical reflector and the second optical reflector form an optical resonant cavity of the hybrid integrated laser;

the semiconductor optical amplifying element and the phase region are both located within the optical resonator; the phase region is integrated on the first chip or the second chip and is used for controlling the optical wavelength of the spectral passband in the optical resonant cavity after the first optical reflector and the second optical reflector are cascaded to meet a resonance condition;

wherein the second light reflector comprises a Sagnac reflector or a reflective end surface disposed on a waveguide in the semiconductor optical amplification element.

2. The hybrid integrated laser of claim 1,

the semiconductor optical amplifying element comprises a straight waveguide and a first semiconductor optical amplifier;

the second optical reflector comprises the reflecting end face, the reflecting end face is arranged on the first port of the straight waveguide, and the second port of the straight waveguide is positioned on the end face of the first chip and serves as an optical transmission end; the first end of the DBR reflector is optically coupled with the light transmission end, and a part of laser light in the optical resonant cavity is output through the second end of the DBR reflector;

the straight waveguide is a linear active waveguide which is a waveguide inside the first semiconductor optical amplifier; or, the straight waveguide is a linear passive waveguide and the waveguide inside the first semiconductor optical amplifier is a straight waveguide or a bent waveguide.

3. The hybrid integrated laser according to claim 2, wherein a core layer material of the optical transmission waveguide of the second chip is thin-film lithium niobate, and the second chip is further integrated with a mach-zehnder modulator;

a first end of the mach-zehnder modulator is connected to a second end of the first optical reflector via an optical transmission waveguide in the second chip, and the second end of the mach-zehnder modulator outputs the laser light output from the second end of the first optical reflector.

4. The hybrid integrated laser of claim 1,

the semiconductor optical amplifying element comprises a U-shaped waveguide and a first semiconductor optical amplifier; two ports of the U-shaped waveguide are respectively connected with the corresponding straight waveguides in the first chip, and two sections of the straight waveguides corresponding to the two ports of the U-shaped waveguide respectively extend to the same end face of the first chip, so that a first optical transmission end and a second optical transmission end are formed on the end face of the first chip;

the second light reflector comprises a Sagnac reflector; a first end of the Sagnac reflector is optically coupled to the first light transmission end, a first end of the DBR reflector is optically coupled to the second light transmission end, and a portion of the laser light in the optical resonant cavity is output through a second end of the Sagnac reflector or a second end of the DBR reflector;

the U-shaped waveguide is a U-shaped active waveguide and the U-shaped active waveguide is a waveguide inside the first semiconductor optical amplifier; or the U-shaped waveguide is a U-shaped passive waveguide and the waveguide inside the first semiconductor optical amplifier is a straight waveguide or a bent waveguide.

5. The hybrid integrated laser according to claim 4, wherein the core material of the optical transmission waveguide of the second chip is thin-film lithium niobate, and the second chip further integrates a Mach-Zehnder modulator;

a first end of the mach-zehnder modulator is connected to a second end of the Sagnac reflector through an optical transmission waveguide in the second chip, and the second end of the mach-zehnder modulator outputs laser light output by the second end of the Sagnac reflector.

6. The hybrid integrated laser as claimed in claim 3 or 5, further comprising: a second semiconductor optical amplifier;

the second semiconductor optical amplifier is used for amplifying and outputting the laser light output by the second end of the Mach-Zehnder modulator.

7. The hybrid integrated laser as claimed in claim 1, wherein an antireflection film is provided on at least one of the end faces of the first chip and the second chip to be optically coupled.

8. The hybrid integrated laser of claim 1, further comprising: a microlens;

the first chip and the second chip are optically coupled through the micro lens, and/or the laser output end face of the hybrid integrated laser and an external optical fiber are optically coupled through the micro lens.

9. The hybrid integrated laser of claim 1, further comprising: an optical isolator;

the optical isolator is arranged between the laser output end face of the hybrid integrated laser and the external optical fiber.

10. A multi-channel hybrid integrated laser, comprising: a plurality of hybrid integrated lasers as claimed in any one of claims 1 to 9;

the plurality of hybrid integrated lasers share the same first chip and share the same second chip.

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