CN116865090A - High-power narrow-linewidth external cavity semiconductor laser - Google Patents
High-power narrow-linewidth external cavity semiconductor laser Download PDFInfo
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
- H01S5/1003—Waveguide having a modified shape along the axis, e.g. branched, curved, tapered, voids
- H01S5/1014—Tapered waveguide, e.g. spotsize converter
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/02—Structural details or components not essential to laser action
- H01S5/024—Arrangements for thermal management
- H01S5/02407—Active cooling, e.g. the laser temperature is controlled by a thermo-electric cooler or water cooling
- H01S5/02415—Active cooling, e.g. the laser temperature is controlled by a thermo-electric cooler or water cooling by using a thermo-electric cooler [TEC], e.g. Peltier element
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/02—Structural details or components not essential to laser action
- H01S5/024—Arrangements for thermal management
- H01S5/02476—Heat spreaders, i.e. improving heat flow between laser chip and heat dissipating elements
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
- H01S5/14—External cavity lasers
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Abstract
The invention provides a high-power narrow-linewidth external cavity semiconductor laser. The structure of the laser comprises a laser gain chip, two spot-size converters, a grating waveguide structure, a semiconductor optical amplifier, a semiconductor refrigerator, a heat sink and a thermistor. The laser gain chip generates optical signals and enters the grating waveguide structure through the mode spot converter, the grating waveguide structure reflects light meeting a specific mode back to the laser gain chip for amplification, and laser is amplified in power through the semiconductor optical amplifier and output after multiple round trips are completed. The high-power narrow-linewidth external cavity semiconductor laser provided by the invention adopts a grating waveguide structure of a columnar array, has extremely low cavity loss, and can improve the effective cavity length to press the narrow linewidth; the mode spot-size converter adopting the ridge waveguide wedge-shaped gradual change structure improves the optical coupling efficiency, thereby reducing the energy loss; the semiconductor optical amplifier is integrated, so that high-power output of the laser is realized, and a thought is provided for the design of the high-power narrow-linewidth laser.
Description
Technical Field
The invention relates to the field of lasers, in particular to a high-power narrow-linewidth external cavity semiconductor laser.
Background
With the vigorous development of coherent optical communication, optical precision measurement, laser radar represented by autopilot and other fields, high-performance narrow-linewidth lasers are rapidly developed. Especially under the drive of new business and application, the data flow is in explosive growth, and the laser used as the pumping source of the communication carrier has higher output power and better spectral characteristics. Accordingly, there is an increasing demand for narrow linewidth semiconductor lasers with high output power, low relative intensity noise. Limited by chip waveguide loss, coupling mode, and active chip gain, achieving both high power and narrow linewidth presents challenges.
Narrow linewidth semiconductor lasers are generally classified into monolithic and external cavity type lasers according to the frequency selective structure. Monolithic semiconductor lasers typically integrate a grating or special waveguide structure within the active cavity, such as a distributed feedback semiconductor laser (Distributed Feedback, DFB), a distributed bragg reflector semiconductor laser (Distributed Bragg Reflector, DBR), etc. The laser has high integration level, small size, complex structure and high manufacturing process difficulty. At the same time, on-chip waveguide losses limit the grating length to below a few millimeters and require higher refractive index perturbations to the waveguide to increase the net reflection, which limits the output power of the laser and thus cannot meet the ever-increasing performance demands.
The external cavity type laser mainly comprises a blazed grating type, a volume holographic grating type, an optical cavity type and a planar waveguide type in structure, wherein the planar waveguide type is an important application of a photon integration technology, and provides more diversified and flexible choices for narrow-band filtering and optical feedback devices. The waveguide Bragg grating (Waveguide Bragg Grating, WBG) has the characteristics of small volume, high integration level and the like as a filtering device, and can realize various different spectral responses by changing parameters such as the period, the refractive index, the phase and the like of the grating. With the increasing performance requirements of devices, higher requirements are also being placed on the design of gratings.
Disclosure of Invention
The invention aims to provide a high-power narrow-linewidth external cavity semiconductor laser, which aims to solve the problems of low output power, high waveguide loss and the like of the traditional laser.
The invention is realized in the following way:
a high-power narrow-linewidth external cavity semiconductor laser comprises a laser gain chip, two mode spot converters, a grating waveguide structure, a semiconductor optical amplifier, a semiconductor refrigerator, a heat sink and a thermistor; the two spot-size converters are a first spot-size converter and a second spot-size converter respectively; the laser gain chip, the first spot-size converter, the grating waveguide structure, the second spot-size converter and the semiconductor optical amplifier are sequentially arranged along an optical path and are fixed on a heat sink together with the thermistor through a bonding process, and the heat sink is fixed on the semiconductor refrigerator through a welding process;
the gain chip of the laser is used for generating optical signals, the two spot-size converters are used for enabling the end faces of the gain waveguide and the grating waveguide to be coupled and matched, and the grating waveguide structure is used for realizing line width narrowing of the laser; the laser gain chip, the first mode spot converter and the grating waveguide structure form an outer cavity of the laser together to oscillate the laser;
the laser gain chip emits laser under the effect of injection current, the laser is injected into the grating waveguide structure after passing through the first mode spot converter, the grating waveguide structure reflects part of light back to the first mode spot converter according to an incident light path after passing through a mode selection and enters the laser gain chip, and the laser oscillation process is repeated after one round trip is completed; the laser oscillated for a plurality of times passes through the second spot-size converter and then is amplified again in the semiconductor optical amplifier and output;
the semiconductor refrigerator, the heat sink and the thermistor form a temperature control loop, the temperature information of the laser gain chip, the grating waveguide structure and the semiconductor optical amplifier is obtained through the thermistor on the heat sink, and the whole temperature is controlled through the semiconductor refrigerator, so that the temperature of the whole structure is stabilized.
The laser gain chip is a multi-quantum well reflection type optical amplifier, the laser gain chip is of a buried heterojunction structure or a ridge waveguide structure, the laser gain chip is made of InP (substrate)/InGaAsP (quantum well active material), and the laser gain chip is of a curved waveguide structure; the two end faces of the laser gain chip are respectively plated with a high-reflection film and a high-transmission film, and laser signals are emitted from the high-transmission films.
The laser gain chip amplifies photons generated by spontaneous radiation by utilizing the gain characteristic of the active material of the laser gain chip, thereby realizing light output.
The waveguide light-exiting end face inside the laser gain chip is not perpendicular to the natural cleavage cavity face of the chip, but is at a small angle, the mode reflection coefficient can be reduced to reduce the effective reflectivity of the end face, and the opposite end face is perpendicular to perform optical oscillation by light back and forth between the external grating and the perpendicular end face side of the laser gain chip. The laser gain chip presents a certain angle during integration, so that the light path of the light-emitting end face is perpendicular to the end face of the first mode spot-size converter, and power loss is reduced.
The two mode spot converters have the same structure and both adopt ridge waveguide wedge-shaped gradual change structures, and specifically comprise three parts, namely a ridge waveguide, a cone-shaped gradual change waveguide and a ridge widening waveguide, which are connected in sequence; the spot-size converter is made of silicon nitride material, indium phosphide material or lithium niobate material. The first mode spot converter is connected with the laser gain chip and the grating waveguide structure, the ridge waveguide of the first mode spot converter is connected with the laser gain chip, and the ridge widening waveguide is connected with the grating waveguide structure; the second mode spot converter is connected with the grating waveguide structure and the semiconductor optical amplifier, and the ridge widening waveguide of the second mode spot converter is connected with the grating waveguide structure, and the ridge waveguide of the second mode spot converter is connected with the semiconductor optical amplifier.
The grating waveguide structure adopts a cylindrical grating waveguide; the grating waveguide structure is a straight-through structure and comprises a strip waveguide and cylindrical waveguides uniformly distributed on two sides of the strip waveguide; the grating waveguide structure is made of silicon nitride material or silicon dioxide material.
The semiconductor optical amplifier amplifies an incident optical signal by stimulated emission; the semiconductor optical amplifier is provided with an antireflection film on the light-emitting end face, and the inclined waveguide is adopted to incline the strip-shaped active area and the normal cleavage surface so as to reduce the reflectivity.
The semiconductor refrigerator, the heat sink and the thermistor form a temperature control loop, and the temperatures of the laser gain chip, the grating waveguide structure and the semiconductor optical amplifier are precisely controlled; by controlling the temperature of the laser, the laser phase is maintained constant, maintaining the laser at the same operating point as its associated output characteristics.
The heat sink is made of tungsten copper alloy, silicon carbide or aluminum nitride ceramic material; the heat sink is used for radiating heat and transmitting the temperature of each device to the thermistor and the semiconductor refrigerator.
The thermistor is positioned at one side of the laser gain chip and avoids the light path; the thermistor is located close to the laser gain chip.
The high-power narrow-linewidth external cavity semiconductor laser provided by the invention adopts a grating waveguide structure of a columnar array, has extremely low cavity loss, and can improve the effective cavity length to press the narrow linewidth; the mode spot-size converter adopting the ridge waveguide wedge-shaped gradual change structure improves the optical coupling efficiency, thereby reducing the energy loss; the semiconductor optical amplifier is integrated, and the high-power output of the laser is realized.
The invention has the following beneficial effects:
1. the high-power narrow-linewidth external cavity semiconductor laser provided by the invention can realize longer effective cavity length and higher mode selectivity by integrating the low-loss cylindrical grating waveguide structure, and can elongate the whole waveguide cavity length, thereby achieving the purpose of narrowing linewidth and providing more diversified and flexible choices for narrow-band filtering and optical feedback devices in the external cavity feedback semiconductor laser.
2. The high-power narrow-linewidth external cavity semiconductor laser provided by the invention can simultaneously restrict light waves transmitted in the horizontal and vertical directions through the integrated ridge waveguide wedge-shaped gradual change structure mode spot converter, solves the problem of mode mismatch in an optical device and a waveguide, reduces the coupling loss between chips, and realizes the efficient coupling of light between an optical fiber and an integrated photon chip.
3. The high-power narrow-linewidth external cavity semiconductor laser provided by the invention realizes high-power laser output through the integrated semiconductor optical amplifier, avoids complex improvement on a chip light source, and greatly simplifies the preparation process.
4. According to the high-power narrow-linewidth external cavity semiconductor laser provided by the invention, the overall control of the laser temperature is realized through the temperature control loop, so that the influence of temperature fluctuation on the cavity length of the resonant cavity is avoided, and the stability of the output wavelength is further influenced. In addition, a quasi-monolithic integrated structure is formed through a bonding process, which is beneficial to reducing the volume and manufacturing cost of the device.
Drawings
Fig. 1 is a top view of a high-power narrow linewidth external cavity semiconductor laser according to an embodiment of the present invention.
Fig. 2 is a front view of a high-power narrow linewidth external cavity semiconductor laser according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a spot-size converter according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of a grating waveguide structure according to an embodiment of the present invention.
Wherein: 1. a semiconductor refrigerator; 2. a heat sink; 3. a thermistor; 4. a laser gain chip; 5. a first spot-size converter; 6. a grating waveguide structure; 7. a second spot-size converter; 8. a semiconductor optical amplifier.
Detailed Description
As shown in fig. 1 and 2, the high-power narrow-linewidth external cavity semiconductor laser provided by the invention comprises a semiconductor refrigerator 1, a heat sink 2, a thermistor 3, a laser gain chip 4, a first spot-size converter 5, a grating waveguide structure 6, a second spot-size converter 7 and a semiconductor optical amplifier 8. The laser gain chip 4, the first spot-size converter 5, the grating waveguide structure 6, the second spot-size converter 7 and the semiconductor optical amplifier 8 are sequentially arranged from left to right along the optical path, and are fixed on the heat sink 2 together with the thermistor 3 through a bonding process to form a quasi-monolithic integrated structure, and the heat sink 2 is fixed on the semiconductor refrigerator 1 through a welding process.
The semiconductor refrigerator 1, the heat sink 2 and the thermistor 3 form a temperature control loop to precisely control the temperatures of the laser gain chip 4, the grating waveguide structure 6 and the semiconductor optical amplifier 8; by controlling the temperature of the laser, the laser phase is maintained constant, maintaining the laser at the same operating point as its associated output characteristics.
The heat sink 2 is made of tungsten copper alloy, silicon carbide or aluminum nitride ceramic material; the heat sink 2 is used for dissipating heat and transferring the temperature of the devices (the devices refer to the laser gain chip 4, the grating waveguide structure 6 and the semiconductor optical amplifier 8) to the thermistor 3 and the semiconductor refrigerator 1.
The thermistor 3 is positioned at one side of the laser gain chip 4 and avoids the light path; the thermistor 3 is located close to the laser gain chip 4.
The waveguides in the laser gain chip 4 and the semiconductor optical amplifier 8 are gain waveguides, and the waveguides in the grating waveguide structure 6 are inorganic waveguides (or called grating waveguides).
The laser gain chip 4 is used for generating optical signals, the first spot-size converter 5 is used for enabling the end faces of the laser gain chip 4 and the grating waveguide structure 6 to be coupled and matched, the grating waveguide structure 6 is used for realizing line width narrowing of a laser, and the laser gain chip 4, the first spot-size converter 5 and the grating waveguide structure 6 jointly form an outer cavity of the laser to oscillate the laser.
The material used for the laser gain chip 4 is InP (substrate)/InGaAsP (quantum well active material); the two end faces of the laser gain chip 4 are respectively plated with a high-reflection film and a high-transmission film (the left end is the high-reflection film and the right end is the high-transmission film in fig. 1), and laser signals are emitted from the high-transmission film.
The laser gain chip 4 amplifies photons generated by spontaneous radiation by utilizing the gain characteristic of the active material of the laser gain chip, so that light output is realized; the active material of the laser gain chip 4 is a quantum well structure, and the gain comes from photons generated by electron transitions between discrete conduction band energy levels and discrete valence band energy levels in the well; the laser gain chip 4 adopts a buried heterojunction structure or a ridge waveguide structure.
With reference to fig. 1, the laser gain chip 4 adopts a curved waveguide structure, namely: the light-emitting end is a bending section, so that the effective reflectivity of the light-emitting end surface of the chip is effectively reduced, the influence of the effective reflectivity of the chip on the self-feedback longitudinal mode is reduced, and the accuracy and single-mode stability of the output wavelength of the external cavity laser are improved. The light-emitting end face of the waveguide inside the laser gain chip 4 is not perpendicular to the natural cleavage cavity face of the chip, but is at a small angle (for example, about 8 ° as shown in fig. 1), so that the mode reflection coefficient can be reduced to reduce the effective reflectivity of the end face, the opposite end faces are perpendicular (i.e., the two end faces of the laser gain chip 4 are perpendicular to the end face of the grating waveguide structure 6), and the laser signal oscillates back and forth between the grating waveguide structure 6 and the laser gain chip 4 to compress the narrow linewidth. The laser gain chip 4 is disposed obliquely upwards (corresponding to the above, also 8 °) during integration, so that the light path of the light-emitting end face is perpendicular to the end face of the first spot-size converter 5 (i.e., the light coming out from the laser gain chip 4 enters the first spot-size converter 5 horizontally), so as to reduce power loss.
The laser gain chip 4 is a multi-quantum hydrazine reflection type optical amplifier and is used for generating optical signals and amplifying signal power, and has the advantages of high power, good frequency stability and the like, and meanwhile, the laser gain chip is small in size, low in power consumption and easy to integrate; the optical signal generated by which is coupled into the grating waveguide structure 6 by the first spot-size converter 5 at an oblique angle (e.g. 10 deg.).
The first and second spot-size converters 5, 7 are specially designed waveguide structures for end-face coupling matching of gain and inorganic waveguides. The optical coupling efficiency is improved by changing the spot size, while the design also has a larger operating bandwidth and lower polarization dependence. The first and second spot-size converters 5 and 7 are identical in structure. For example, as shown in fig. 3, the first mode spot-size converter 5 is a ridge waveguide wedge-shaped graded structure, and sequentially includes three parts (including a substrate at the bottom, and a confinement structure at the bottom) of a ridge waveguide, a tapered graded waveguide, and a ridge widening waveguide. The ridge waveguide has a width smaller than the width of the ridge widening waveguide.
The two spot-size converters are made of silicon nitride material, indium phosphide material or lithium niobate material. The first mode spot-size converter 5 is used for connecting the laser gain chip 4 and the grating waveguide structure 6, and the ridge waveguide of the first mode spot-size converter 5 is connected with the laser gain chip 4, and the ridge widening waveguide is connected with the grating waveguide structure 6. The second mode spot-size converter 7 is used for connecting the grating waveguide structure 6 and the semiconductor optical amplifier 8, the ridge-shaped widening waveguide of the second mode spot-size converter 7 is connected with the grating waveguide structure 6, and the ridge-shaped waveguide is connected with the semiconductor optical amplifier 8. For the first mode spot-size converter 5, the laser is first transmitted in the ridge waveguide, the waveguide width increases with the transmission distance, the mode field area increases with the transmission distance, and finally, the mode field with small size in the ridge waveguide is stably converted into the mode field with large size in the ridge widening waveguide through the taper gradual change waveguide with certain length, and vice versa.
The spot-size converter can improve optical coupling efficiency by changing the spot size, thereby reducing energy loss. The wedge-shaped mode spot converter is based on the mode field diffusion principle and has the remarkable characteristics of insensitive loss to wavelength, small polarization correlation, high coupling efficiency, easy packaging, easy integration and the like.
The grating waveguide structure 6 is placed after the first mode spot-size converter 5, so as to feed back the light emitted by the laser gain chip 4 after mode selection to the laser gain chip 4, and the introduction of the grating waveguide structure 6 increases the photon lifetime of the system, thereby narrowing the linewidth. As shown in fig. 4, the grating waveguide structure is composed of a stripe waveguide and columnar waveguides uniformly distributed on two sides of the stripe waveguide, wherein the stripe waveguide is a straight stripe structure, and the columnar waveguides distributed on two sides of the stripe waveguide form two columns of columnar arrays. The grating waveguide structure 6 in the invention is composed of a straight waveguide and a columnar waveguide, and the traditional fence-shaped structure is abandoned. The straight-through waveguide structure is straight-forward and does not need to adopt a ring structure for coupling transmission. The bottom of the grating waveguide structure is a substrate, the outside is coated with a protective layer (usually oxide material), and the substrate, the protective layer and the grating waveguide structure together form a grating layer. The grating waveguide structure 6 has very low cavity losses and can achieve a longer effective cavity length and higher mode selectivity. The grating waveguide structure 6 is made of silicon nitride material or silicon dioxide material. The grating waveguide structure is positioned in the oxide protective layer so as to reduce the use loss and prolong the service life of the laser.
The laser gain chip 4 emits laser under the effect of injection current, the laser is injected into the grating waveguide structure 6 from the high-permeability film end surface of the laser gain chip 4 through the first mode spot converter 5, the grating waveguide structure 6 reflects a part of the laser back to the first mode spot converter 5 according to an incident light path after selecting a mode, and then enters the laser gain chip 4, and the process is repeated after one round trip is completed; the final laser after multiple laser oscillations (at this time, the mode selection is completed, the laser line width is narrowed) enters the semiconductor optical amplifier 8 through the second mode spot converter 7, and the laser performs optical power amplification again in the semiconductor optical amplifier 8 and outputs, so as to realize high-power laser output. The semiconductor optical amplifier 8 amplifies an incident optical signal by stimulated emission; the semiconductor optical amplifier 8 is coated with an antireflection film on the light-emitting end face, and uses an inclined waveguide (inclined line in fig. 1) to incline the strip-shaped active region (i.e., the region through which the inclined waveguide passes) from the natural cleavage plane (corresponding to the above 10 °) to reduce the reflectivity.
Claims (9)
1. The high-power narrow-linewidth external cavity semiconductor laser is characterized by comprising a semiconductor refrigerator, a heat sink arranged on the semiconductor refrigerator, a laser gain chip positioned on the heat sink, a first spot-size converter, a grating waveguide structure, a second spot-size converter, a semiconductor optical amplifier and a thermistor; the laser gain chip, the first mode spot converter, the grating waveguide structure, the second mode spot converter and the semiconductor optical amplifier are sequentially arranged along an optical path;
the gain chip of the laser is used for generating optical signals, the two spot-size converters are used for enabling the end faces of the gain waveguide and the grating waveguide to be coupled and matched, and the grating waveguide structure is used for realizing line width narrowing of the laser; the laser gain chip, the first mode spot converter and the grating waveguide structure form an outer cavity of the laser together to oscillate laser;
the laser gain chip emits laser under the effect of injection current, the laser is injected into the grating waveguide structure after passing through the first mode spot converter, the grating waveguide structure reflects part of light back to the first mode spot converter according to an incident light path after passing through a mode selection and enters the laser gain chip, and the laser oscillation process is repeated after one round trip is completed; the laser oscillated for a plurality of times passes through the second spot-size converter and then is amplified again in the semiconductor optical amplifier and output;
the semiconductor refrigerator, the heat sink and the thermistor form a temperature control loop to control the temperature of the laser gain chip, the grating waveguide structure and the semiconductor optical amplifier.
2. The high power narrow linewidth external cavity semiconductor laser of claim 1 wherein said laser gain chip is a multiple quantum well reflective optical amplifier using InP/InGaAsP; the laser gain chip is of a buried heterojunction structure or a ridge waveguide structure; and the two end surfaces of the laser gain chip are respectively plated with a high-reflection film and a high-transmission film.
3. The high-power narrow linewidth external cavity semiconductor laser as claimed in claim 1 wherein the waveguide light-emitting end surface inside the laser gain chip is not perpendicular to the natural cleavage cavity surface of the chip, but is at a bend angle; the gain chip of the laser is in a set angle during integration, so that the light path of the light-emitting end face is perpendicular to the end face of the first spot-size converter.
4. The high-power narrow linewidth external cavity semiconductor laser as claimed in claim 1 wherein the first and second mode spot-size converters are each of a ridge waveguide wedge-shaped graded structure, specifically comprising three parts in order, namely a ridge waveguide, a taper graded waveguide and a ridge widening waveguide; the first and second spot-size converters are made of silicon nitride material, indium phosphide material or lithium niobate material.
5. The high power narrow linewidth external cavity semiconductor laser of claim 4 wherein the first mode spot-size converter connects the laser gain chip with the grating waveguide structure and the ridge waveguide of the first mode spot-size converter connects the laser gain chip and the ridge widening waveguide connects the grating waveguide structure; the second mode spot converter is connected with the grating waveguide structure and the semiconductor optical amplifier, and the ridge widening waveguide of the second mode spot converter is connected with the grating waveguide structure, and the ridge waveguide of the second mode spot converter is connected with the semiconductor optical amplifier.
6. The high-power narrow linewidth external cavity semiconductor laser as in claim 1 wherein said grating waveguide structure is a straight-through structure comprising a strip waveguide and columnar waveguides uniformly distributed on both sides of said strip waveguide; the grating waveguide structure is made of silicon nitride material or silicon dioxide material.
7. The high power narrow linewidth external cavity semiconductor laser as in claim 1 wherein said semiconductor optical amplifier employs a slanted waveguide to tilt the stripe-shaped active region from the natural cleavage plane.
8. The high power narrow linewidth external cavity semiconductor laser as in claim 1 wherein said thermistor is located on one side of the laser gain chip and avoids the optical path.
9. The high power narrow linewidth external cavity semiconductor laser as in claim 1 wherein said heat sink is a tungsten copper alloy, silicon carbide or aluminum nitride ceramic material.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310964969.XA CN116865090A (en) | 2023-08-02 | 2023-08-02 | High-power narrow-linewidth external cavity semiconductor laser |
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| CN202310964969.XA CN116865090A (en) | 2023-08-02 | 2023-08-02 | High-power narrow-linewidth external cavity semiconductor laser |
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| CN202310964969.XA Pending CN116865090A (en) | 2023-08-02 | 2023-08-02 | High-power narrow-linewidth external cavity semiconductor laser |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118630573A (en) * | 2024-08-13 | 2024-09-10 | 中国科学院长春光学精密机械与物理研究所 | Linearly polarized narrow linewidth external cavity semiconductor laser |
| CN119029667A (en) * | 2024-07-29 | 2024-11-26 | 长春理工大学 | A Laterally Coupled Beam-Condensing Ridge Waveguide Distributed Feedback Semiconductor Laser |
| CN119695630A (en) * | 2025-02-26 | 2025-03-25 | 哈尔滨工业大学(深圳)(哈尔滨工业大学深圳科技创新研究院) | Antimonide single transverse mode external cavity laser |
| CN120357269A (en) * | 2025-06-25 | 2025-07-22 | 天府兴隆湖实验室 | Waveguide external cavity laser |
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2023
- 2023-08-02 CN CN202310964969.XA patent/CN116865090A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN119029667A (en) * | 2024-07-29 | 2024-11-26 | 长春理工大学 | A Laterally Coupled Beam-Condensing Ridge Waveguide Distributed Feedback Semiconductor Laser |
| CN118630573A (en) * | 2024-08-13 | 2024-09-10 | 中国科学院长春光学精密机械与物理研究所 | Linearly polarized narrow linewidth external cavity semiconductor laser |
| CN119695630A (en) * | 2025-02-26 | 2025-03-25 | 哈尔滨工业大学(深圳)(哈尔滨工业大学深圳科技创新研究院) | Antimonide single transverse mode external cavity laser |
| CN120357269A (en) * | 2025-06-25 | 2025-07-22 | 天府兴隆湖实验室 | Waveguide external cavity laser |
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