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

Background

Conventional semiconductor lasers mainly include a DFB (Distributed Feedback Laser), a DBR (Distributed Bragg Reflector) and an EML (Electro-absorption Modulated Laser). The two lasers can be used as a continuous wave laser or an Electro-optical intensity modulation laser, and the EML is monolithic integration of a DFB laser and an EAM (Electro Absorption Modulator).

The DFB laser has small size and low cost because the Bragg grating for filtering and selecting the mode is distributed in the active gain area, thereby having wide application in the fields of optical communication and optical sensing. But its disadvantage is that the bandwidth of electro-optical modulation is low due to relaxation oscillation, and the modulation chirp is large, so it is not suitable for wide-band and long-distance transmission.

The DBR laser is a continuous wave laser that has a small number of applications because the bragg grating for filtering and mode selection is disposed outside the active gain region, but the laser has a narrower line width than the DFB laser, and has no improvement in modulation bandwidth and modulation chirp, and the size of the DBR laser is larger than that of the DFB laser. The DBR laser is mainly applied to the construction of a wavelength tunable laser by using a vernier effect, but most of the prior art is based on monolithic integration of active region gain region materials, although the integration level is high, the process implementation difficulty is high, and the cost is high.

EML uses DFB lasers as continuous wave lasers with electro-absorption modulators to achieve optical intensity modulation, improving on modulation bandwidth and chirp, but still difficult in large bandwidth, long distance transmission applications.

Disclosure of Invention

The invention provides a hybrid integrated laser, which is used for realizing a narrow linewidth semiconductor laser, ensuring that the narrow linewidth semiconductor laser has lower process difficulty and manufacturing cost, further realizing high-speed modulation with large bandwidth and adjustable chirp of the narrow linewidth semiconductor laser on the basis, and meeting the application requirement of medium-distance and long-distance optical communication.

In a first aspect, an embodiment of the present invention provides a hybrid integrated laser, including: 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.

Optionally, 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.

Optionally, 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.

Optionally, 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 with the first light transmission end, a first end of the DBR reflector is optically coupled with the second light transmission end, and a part of 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.

Optionally, 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 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.

Optionally, the hybrid integrated laser further comprises: 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 antireflection film is disposed on at least one of the end surfaces of the first chip and the second chip that are optically coupled.

Optionally, the hybrid integrated laser further comprises: 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.

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

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

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 invention comprises an optical gain area, a first optical reflector, a second optical reflector and a phase area; the optical gain region is disposed on the first chip and includes a semiconductor optical amplifying element.

The narrow-linewidth semiconductor laser is enabled to be narrow by arranging the first optical reflector to comprise the DBR reflector, so that the narrow linewidth requirement of a coherent optical communication system on the laser is met, meanwhile, the second optical reflector comprises the Sagnac reflector or a reflecting end face arranged on a waveguide in a semiconductor optical amplification element, 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 a hybrid integrated laser, an optical gain area and a phase area are both positioned in the optical resonant cavity, the first optical reflector is integrated on the second chip, and the second optical reflector is integrated on the first chip or the second chip, so that the narrow-linewidth semiconductor laser is enabled to have low process difficulty and manufacturing cost in an inter-chip hybrid integration mode while the narrow-linewidth semiconductor laser is achieved.

And, integrating the optical gain region and the first light reflector on the first chip and the second chip, respectively, the first chip and the second chip may be different in material. Under the condition that the second chip is arranged to adopt the thin-film lithium niobate wafer, the high-speed electro-optical modulator can be further integrated in the second chip, so that a hybrid integrated laser capable of being modulated at high speed is realized, the bandwidth and the transmission distance are greatly increased, namely, the high-speed modulation with the narrow-linewidth semiconductor laser, large bandwidth and adjustable chirp is realized, and the application requirement of medium-distance and long-distance optical communication is met.

It should be understood that the statements in this section do not necessarily identify key or critical features of the embodiments of the present invention, nor do they necessarily limit the scope of the invention. Other features of the present invention will become apparent from the following description.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic top view of a hybrid integrated laser according to an embodiment of the present invention;

FIG. 2 is a light reflection spectrum of a hybrid integrated laser according to an embodiment of the present invention;

fig. 3 is a schematic top view of another hybrid integrated laser according to an embodiment of the present invention;

fig. 4 is a schematic top view of another hybrid integrated laser according to an embodiment of the present invention;

fig. 5 is a schematic top view of another hybrid integrated laser according to an embodiment of the present invention;

fig. 6 is a schematic top view of another hybrid integrated laser according to an embodiment of the present invention;

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

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, 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 in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Fig. 1 is a schematic top view of a hybrid integrated laser according to an embodiment of the present invention. Referring to fig. 1, a hybrid integrated laser 10 includes: an optical gain section, a first optical reflector including a DBR reflector 121, a second optical reflector, and a phase section 122; the optical gain region is arranged on the first chip 11, and comprises a semiconductor optical amplifying element; the first optical reflector is integrated on the second chip 12, the second optical reflector is integrated on the first chip 11 or the second chip 12, and the first optical reflector, the second optical reflector and the optical waveguide loop between the first optical reflector and the second optical reflector form an optical resonant cavity of the hybrid integrated laser 10; the semiconductor optical amplifying element and the phase region 122 are both located in the optical resonant cavity, the phase region 122 is integrated on the first chip 11 or the second chip 12, and the phase region 122 is used for controlling the optical wavelength of the spectral passband after the first optical reflector and the second optical reflector are cascaded in the optical resonant cavity to meet the resonance condition; wherein the second light reflector comprises a Sagnac reflector or a reflective end surface 1111 provided on a waveguide in the semiconductor optical amplifying element.

In particular, the optical gain region is used to implement an optical gain function. The semiconductor optical amplifying element comprises a semiconductor optical amplifier and a waveguide. The first optical reflector, the second optical reflector and the optical waveguide circuit therebetween form an optical resonant cavity of the hybrid integrated laser 10, the optical waveguide circuit may include an optical transmission waveguide in the first chip 11 and/or the second chip 12, the semiconductor optical amplifying element and the phase section 122 are located in the optical resonant cavity, and the phase section 122 is configured to adjust a phase of light in the optical resonant cavity, that is, the phase of light makes an integer multiple of 2 pi when the light makes a round trip in the optical resonant cavity. Light within the optical cavity passes through the optical gain and phase sections 122 to oscillate back and forth between the first and second optical reflectors.

In the embodiment of the present invention, the first optical reflector includes the DBR reflector 121, and the DBR reflector 121 is used as a narrow-band filter, so as to realize a function of mode selection and output from a plurality of longitudinal modes meeting resonance conditions in the optical resonant cavity, so that the line width of laser output by the laser 10 is narrow, and a requirement of a coherent optical communication system on the narrow line width of the laser 10 is met; fig. 2 is a light reflection spectrum diagram of a hybrid integrated laser 10 according to an embodiment of the present invention, where the horizontal axis represents the optical wavelength λ and the vertical axis represents the reflectivity dB, as schematically illustrated in fig. 2, the light reflection spectrum diagram includes the passband center wavelength λ c, and the DBR reflector 121 partially reflects at the passband center wavelength λ c and partially transmits as the laser output. On this basis, the optical gain region is arranged on the first chip 11, the first optical reflector is integrated on the second chip 12, and the second optical reflector is integrated on the first chip 11 or the second chip 12, so that the hybrid integration DBR laser 10 is realized, and the narrow-line-width semiconductor laser 10 is ensured to have lower process difficulty and manufacturing cost through an inter-chip hybrid integration mode while the narrow-line-width semiconductor laser 10 is realized.

Furthermore, 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 is the main inventive concept of the embodiments of the present invention, and the hybrid integrated laser 10 will be described in detail below based on the above technical solutions in both cases where the second light reflector includes a Sagnac reflector or a reflecting end surface provided on a waveguide in the semiconductor optical amplifying element.

Optionally, with continued reference to fig. 1, in one embodiment of the invention: the semiconductor optical amplifying element is a semiconductor optical amplifier 111 with a linear waveguide, which includes a straight waveguide and a first semiconductor optical amplifier, the straight waveguide includes two opposite ports, i.e., a first port and a second port, the first port is provided with a reflective end surface 1111, the second port is located on an end surface of the first chip 11 and serves as an optical transmission end a, and the optical transmission end a is optically coupled to the first end of the DBR reflector 121, so that a part of laser light in the optical resonator is output through the second end of the DBR reflector 121 and serves as laser output of the laser 10; the DBR reflector 121 has a first end and a second end opposite to each other, and the first end and the second end have the same optical properties and are both reflective and transmissive.

Specifically, the DBR reflector 121, the reflective end surface 1111, and the optical waveguide circuit therebetween constitute an optical resonant cavity of the hybrid integrated laser 10. The reflective end surface 1111 is a highly reflective surface. The reflection end surface 1111 may be directly formed by an end surface of the first port, and at this time, it may be set that the reflectivity of the first port end surface is greater than that of the second port end surface, that is, the first port end surface is a high reflection surface, the second port end surface is a low reflection surface, and the first port end surface is a high reflection surface which may be realized by plating a high reflection film on the first port end surface, and the second port end surface is a low reflection surface which may be realized by plating a low reflection film on the second port end surface. High and low reflection films are plated as an alternative, because even if the first and second ports are not plated with films, the reflectivity of the crystal end faces can be matched with the first light reflector to form an optical resonant cavity, and the plating only enables the output light power of the laser 10 to be larger. The reflecting end surface 1111 is exemplarily illustrated on the end surface of the first chip 11 far from the second chip 12 in fig. 1, because the port of the straight waveguide in the semiconductor optical amplification element may extend directly onto the end surface of the first chip 11 or onto the end surface of the first chip 11 through the optical transmission waveguide in the first chip 11.

The embodiment of the present invention integrates the optical gain region and the light reflector on the first chip 11 and the second chip 12, respectively, 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 material of the optical transmission waveguide in the second chip 12 may be thin-film lithium niobate (LiNbO)₃) Silicon (Si), silicon nitride (Si)₃N₄) Or silicon dioxide (SiO)₂)。

On the basis of the foregoing embodiments, optionally, fig. 3 is a schematic top view structure diagram of another hybrid integrated laser provided in an embodiment of the present invention, and referring to fig. 3, in a case that a core layer material of an optical transmission waveguide in the second chip 12 is thin-film lithium niobate, based on a high-speed electro-optical 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 DBR reflector 121 and the Mach-Zehnder modulator 124 are integrated and cascaded on the second chip 12, so that the hybrid integrated laser 10 capable of high-speed modulation is implemented, a bandwidth and a transmission distance are greatly increased, that is, a narrow-linewidth laser 10 with a large bandwidth and a chirp-adjustable high-speed modulation is implemented, and application requirements of medium-and long-distance optical communication are met.

A first end of the mach-zehnder modulator 124 is connected to a second end of the first optical reflector through an optical transmission waveguide in the second chip 12, and the second end of the mach-zehnder modulator 124 outputs the laser light output from the second end of the first optical reflector as the output laser light of the laser 10; the Mach-Zehnder modulator 124 can adjust the chirp by adjusting the dc bias operating point and the rf voltage of the phase shift arm of the Mach-Zehnder interferometer, and can compensate for fiber dispersion with the 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 increase the bandwidth and the transmission distance.

Optionally, in an embodiment of the present invention, the straight waveguide is a linear active waveguide and the linear active waveguide is a waveguide inside the first semiconductor optical amplifier; alternatively, the straight waveguide is a linear 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 structural diagram of another hybrid integrated laser provided in an embodiment of the present invention, and referring to fig. 4, in another embodiment of the present invention: the semiconductor optical amplifying element is a semiconductor optical amplifier 112 with a U-shaped waveguide, which includes a U-shaped waveguide and a first semiconductor optical amplifier, two ports of the U-shaped waveguide are respectively connected with corresponding light transmission straight waveguides in the first chip 11, and two sections of light transmission straight waveguides corresponding to the two ports of the U-shaped waveguide respectively extend to the same end face of the first chip 11, so that a first light transmission end a1 and a second light transmission end a2 are formed on the end face of the first chip 11; the second light reflector includes a Sagnac reflector 125, a first end of the Sagnac reflector 125 is optically coupled to the first light transmitting end a1, a first end of the DBR reflector 121 is optically coupled to the second light transmitting end a2, and a portion of the laser light in the optical resonant cavity is output through a second end of the Sagnac reflector 125 or a second end of the DBR reflector 121 as the laser light output of the laser 10.

Specifically, the first light transmission end a1 is cascaded with Sagnac reflector 125, the second light transmission end a2 is cascaded with DBR reflector 121, and the DBR reflector 121, Sagnac reflector 125, and the optical waveguide loop therebetween constitute the optical resonant cavity of 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; and when the U-shaped waveguide is a U-shaped passive waveguide, the waveguide in the first semiconductor optical amplifier is a straight waveguide or a bent waveguide.

On the basis of the foregoing embodiments, optionally, fig. 5 is a schematic top view structure diagram of another hybrid integrated laser provided in an embodiment of the present invention, and referring to fig. 5, in a case that a core layer material of an optical transmission waveguide in the second chip 12 is thin film lithium niobate, a mach-zehnder modulator 124 is further integrated on the second chip 12, so as to implement the hybrid integrated laser 10 capable of high-speed modulation, greatly improve a bandwidth and a transmission distance, that is, implement high-speed modulation with a large bandwidth and adjustable chirp of the narrow-linewidth semiconductor laser 10, and meet application requirements of medium-and long-distance optical communication. A first end of the mach-zehnder modulator 124 and a second end of the Sagnac reflector 125 are connected through an optical transmission waveguide in the second chip 12, and a second end of the mach-zehnder modulator 124 outputs the laser light output from the second end of the first optical reflector as the laser light output of the laser 10. In addition, the reflectivity of Sagnac reflector 125 may be designed to a desired value by setting the coupling coefficient of the directional coupler therein; of course, Sagnac reflector 125 may also be cascaded with mach-zehnder modulator 124, where Sagnac reflector 125 is typically designed for high reflectivity.

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 from the second end of the mach-zehnder modulator 124 to improve the output power of the hybrid integrated laser 10, where the laser 10 further includes the second semiconductor optical amplifier is described below by taking the hybrid integrated laser 10 illustrated in fig. 5 as an example:

illustratively, fig. 6 is a schematic top view of another hybrid integrated laser according to an embodiment of the present invention, and referring to fig. 6, the second semiconductor optical amplifier is a semiconductor optical amplifier 113 with a straight waveguide (the same device as the semiconductor optical amplifier 111 with a straight waveguide), the semiconductor optical amplifier 113 with a straight waveguide is integrated on the first chip 11, a first end of the semiconductor optical amplifier 113 with a straight waveguide is connected to a second end of the mach-zehnder modulator 124, a second end of the semiconductor optical amplifier 113 with a straight waveguide amplifies and outputs laser light output from the second end of the mach-zehnder modulator 124, that is, a part of laser light in the optical resonator is output through the second end of the Sagnac reflector 125, the second end of the mach-zehnder modulator 124 and the second end of the semiconductor optical amplifier 113 with a straight waveguide in sequence, thereby increasing the output power of the hybrid integrated laser 10.

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

Specifically, the relationship between the optical gain region and the first chip 11 may be understood as that the chip provided with the optical gain region is the first chip 11, and the relationship between the first optical reflector, the second optical reflector, the mach-zehnder modulator 124 and the second chip 12 may be understood as that the chip integrated with the first optical reflector, the second optical reflector, and the mach-zehnder modulator 124 is the second chip 12, so that the optical coupling between the first chip 11 and the second chip 12 is essentially the optical coupling between the optical reflector and the optical transmission end on the end faces opposite to the first chip 11 and the second chip 12, and with reference to fig. 6, the present embodiment is provided with the antireflection film 123 on at least one of the end faces for optical coupling, so as to ensure the optical transmission efficiency between the optical reflector and the optical transmission end.

Referring to the technical solution of the above embodiment, the laser output end face, that is, the end face of the hybrid integrated laser 10 outputting laser light, may be, for example, the second end of the DBR reflector 121, the second end of the Sagnac reflector 125, the second end of the mach-zehnder modulator 124, or the second end of the semiconductor optical amplifier 113 with a straight waveguide, and the laser output end face is coated with the antireflection film 123 to ensure the laser output efficiency of the laser output end face.

On the basis of the foregoing embodiments, as an implementation manner 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 an 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 light reflector and the light transmission end; the laser output end face of the hybrid integrated laser 10 is optically coupled to the external optical fiber through the micro lens, so as to further improve the light output efficiency of the laser output end face.

On the basis of the foregoing embodiments, as an implementation manner of the present invention, optionally, the hybrid integrated laser 10 further includes: and the optical isolator is arranged between the laser output end face of the hybrid integrated laser 10 and an external optical fiber, namely, the optical isolator is arranged between the laser output end face and the external optical fiber, so that the influence of system echo on the hybrid integrated laser 10 is avoided.

An embodiment of the present invention further provides a multi-channel hybrid integrated laser, and fig. 7 is a schematic top view structure diagram of the multi-channel hybrid integrated laser provided in the embodiment of the present invention. Referring to fig. 7, the multi-channel hybrid integrated laser includes a plurality of hybrid integrated lasers 10 (four hybrid integrated lasers 10 are exemplarily illustrated in fig. 7) implemented as any of the above embodiments, and the plurality of hybrid integrated lasers 10 share the same first chip 11 and the same second chip 12.

Specifically, the optical gain regions of the hybrid integrated lasers 10 are integrated on the same first chip 11, the first optical reflectors of the hybrid integrated lasers 10 are integrated on the same second chip 12, and as exemplarily illustrated in fig. 7, the second optical reflectors of the hybrid integrated lasers 10 each include a reflective end facet 1111. The multi-channel hybrid integrated laser can simultaneously output a plurality of different optical wavelengths as required, and the sharing of the first chip 11 and the second chip 12 can improve the integration level of the multi-channel hybrid integrated laser.

The above-described embodiments should not be construed as limiting the scope of the invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made in accordance with design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in 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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