1106results about "Laser optical resonator construction" patented technology

The invention provides a distributed feedback laser with a double-layer grating structure, and relates to the technical field of lasers, the laser forms an InGaAlAs multi-quantum well active region, an upper sampling grating layer and a lower phase shift grating layer on an n-type InP substrate in sequence, the upper grating layer is designed based on a reconstruction equivalent chirp technology, and the lower phase shift grating layer is designed based on a reconstruction equivalent chirp technology. Two sections of asymmetric modulation areas with sampling periods linearly gradually changing in opposite directions are arranged in the axial direction of the resonant cavity, and the lower grating layer is a quarter-wave phase shift grating matched with the period of the upper seed grating. Through the synergistic effect of equivalent phase modulation and phase shift generated by the double-layer grating, the photon density distribution in the cavity can be improved, the longitudinal space hole burning effect can be weakened, the sensitivity to end face phase fluctuation can be reduced, high single-mode power and large modulation bandwidth can be realized in a wide temperature range, and the double-layer grating is suitable for a high-speed optical communication and coarse wavelength division multiplexing transmission system.

The invention discloses an external cavity tunable laser linewidth compression system for realizing wavelength phase locking based on mutual injection of gain chips. The external cavity tunable laser linewidth compression system comprises a red light semiconductor laser main gain chip, a first collimation optical system, a blazed grating, a tuning rotating mirror, a reflector, a power supply driving system and a double-path feedback amplification system, the double-path feedback amplification system comprises a first secondary gain chip, a second secondary gain chip, a second collimation optical system, a third collimation optical system and a polarization-free beam splitter prism; and the red light semiconductor laser main gain chip, the first secondary gain chip and the second secondary gain chip are all connected with the power supply driving system. Therefore, the technical problems of low output infrared light power, poor stability and narrow mode-hopping-free tuning range in the prior art are solved, and high-power, narrow-linewidth, high-stability and large-range mode-hopping-free continuous tuning red light output can be realized.

The invention discloses a low-divergence-angle narrow-linewidth high-power semiconductor laser. Relates to the technical field of semiconductor lasers, in particular to a low-divergence-angle narrow-linewidth high-power semiconductor laser. According to the invention, the parabolic waveguide structure is etched in the light field expansion area, and the metal reflector is introduced to realize a novel light field expansion and metal reflector integrated structure, and the transverse divergence angle of a laser mode is reduced through the expansion structure at the tail end of the waveguide. The laser comprises a laser gain area, a light field expansion area and a spectrum purification area at the tail of the light field expansion area. The laser gain region, the light field expansion region and the spectrum purification region at the tail part of the light field expansion region are made of the same laser epitaxial material in the longitudinal direction, the laser gain region is adjacent to the light field expansion region along the horizontal light emitting direction, and the light field expansion region is adjacent to the spectrum purification region at the tail part of the light field expansion region along the horizontal light emitting direction; the longitudinal direction is the direction from the substrate to the contact layer.

The invention relates to the technical field of chip preparation, and provides a chip based on an annular photonic crystal and a preparation method thereof. The preparation method comprises the following steps: growing a nucleating layer on a substrate; growing a superlattice structure on one side, away from the substrate, of the nucleating layer; sequentially growing an n-type coating layer, an n-type waveguide layer, a quantum well and a p-type electron blocking layer on one side, deviating from the nucleating layer, of the superlattice structure; etching a plurality of annular cavities on the p-type electron barrier layer to form an annular photonic crystal; growing a p-type extension contact layer on one side, deviating from the quantum well, of the p-type electron blocking layer; and carrying out in-situ annealing treatment. According to the preparation method, the directivity of the photonic band gap can be effectively adjusted, uniform light waves in all directions on the side face can be formed, so that leakage of laser from a non-light-emitting area on the side face is restrained, the light emitting efficiency is improved, the annular photonic crystals are periodically distributed, and the light beam quality is effectively guaranteed.

A chip-scale mode-locked laser including a cavity including a gain medium for amplifying signal electromagnetic radiation (signal) through stimulated emission, the signal comprising a signal wavelength; and a passive or active mode-locking device to enforce pulse formation in the laser. The mode-locking device includes a thin-film waveguide having a thickness on the order of the signal wavelength so as to confine and guide the signal along the thin-film waveguide, and a material comprising a second-order nonlinear susceptibility to enable active or passive mode-locking of the signal. The mode-locking device leads to generation of pulses of the signal outputted from the mode-locked laser.

Heterogeneous photonic circuits comprise a gain section optically coupled to a photonics section. The gain section can include at least one gain waveguide which can be formed from a III-V semiconductor material to provide optical gain. The gain waveguide can be coupled to optical components in the photonics section to form an integrated pump module. The photonics section can include a light-generating photonic circuit, which can comprise at least one waveguide doped with a rare-earth ion or transition-metal ion. Output from the integrated pump module and / or the light-generating photonic circuit can be tunable. Tuning can be implemented with feedback control.

The invention relates to the technical field of semiconductor lasers, in particular to an ultra-narrow linewidth wavelength-adjustable external cavity laser based on a planar metal grating, which comprises a gain chip, and the left end face and the right end face of the gain chip are respectively plated with a high reflection film and a first antireflection film; a planar metal grating waveguide is arranged on the right side of the gain chip, the right end face of the gain chip is aligned and attached to the left end face of the planar metal grating waveguide, and a second antireflection film and a third antireflection film are plated on the left end face and the right end face of the planar metal grating waveguide respectively; the planar metal grating waveguide comprises a grating waveguide substrate, a ridge optical waveguide is arranged on the upper portion of the grating waveguide substrate, an annular resonance optical waveguide is arranged on the front side of the ridge optical waveguide, a planar metal grating is arranged on the upper portion of the ridge optical waveguide, and a top covering layer is arranged on the upper portion of the planar metal grating. Through the centimeter-level metal grating and the low-loss coupling structure, light beam quality with 3dB line width less than 700Hz and M2 less than 0.9 is realized.

The embodiment of the application provides an optical amplifier, an optical assembly, an optical module, an optical communication network system and a detection device, relates to the technical field of semiconductors, and is used for solving the problem of one-way light emission of the optical amplifier. The optical amplifier comprises a waveguide and a photonic crystal. The waveguide comprises a core region and a cladding region arranged at the periphery of the core region. The waveguide further comprises an incident light side, a first light emission side and a second light emission side. The photonic crystal is arranged in the cladding region of the waveguide. The core region is located between the incident light side and the first light emission side, and the photonic crystal is located between the second light emission side and the core region. The photonic crystal is used for receiving incident light from the incident light side and emitting first emitted light and second emitted light. The first emitted light is emitted from the first light emission side, and the second emitted light is emitted from the second light emission side.

The invention belongs to the technical field of optical communication, and particularly relates to a narrow linewidth laser based on a cascaded micro-ring resonant cavity. The laser comprises a semiconductor laser inner cavity module, a gain chip module, a phase shifter, a cascade micro-ring resonant cavity module, a thermal tuning module and an outer cavity reflector. The gain chip is combined with an III-V group material at the top of the silicon waveguide through heterogeneous integration, and adopts an InAlGaAs quantum well to provide high gain; the phase shifter is used for matching the lasing wavelength with the resonant wavelength; the cascaded micro-ring resonant cavity is formed by cascading three micro-rings, and tuning of the laser is realized based on a vernier effect; the thermal tuning module is composed of three semi-annular metal strips and a straight waveguide-shaped metal strip. The outer cavity reflector module adopts a Sagnac ring structure; the laser inner cavity, the gain chip, the cascade micro-ring resonant cavity and the outer cavity reflector are directly connected through silicon waveguides. The laser has the characteristics of narrow linewidth and wide tuning range, is easy to highly integrate and interconnect, and has important application value.

An optical transmitter includes a distributed feedback (DFB) laser having an active region formed as a multiple quantum well (MQW) and a diffraction grating, an electro-absorption (EA) modulator having an absorption region formed as a MQW having a composition different from a composition of the DFB laser, a semiconductor amplifier (SOA) having an active region having a same composition as the composition of the DFB laser, a bent waveguide that rotates a light propagation direction, and a passive waveguide connected to the SOA and including a core having a band gap wavelength shorter than an oscillation wavelength of the DFB laser. A tapered region of the passive waveguide converts a width W1 of the passive waveguide connected to the SOA into a width W2 of a narrow waveguide region of the passive waveguide, and the passive waveguide is in contact with the end surface of the substrate.

The invention relates to the technical field of optoelectronic devices, in particular to a laser based on two different gratings and a metal grating with a phase interval of lambda / 2, which comprises a gain chip, a gain chip optical waveguide, an optical waveguide substrate, an optical waveguide, an annular resonant optical waveguide and a metal BRAGG reflecting grating. A unique outer cavity structure is adopted, a traditional interlayer semiconductor grating is abandoned, a top metal grating is adopted, a traditional DFB sandwich type secondary epitaxy manufacturing process is greatly simplified and avoided, the production cost is reduced, particularly, the metal grating is divided into two parts with similar but different grating constants, and the phase positions of the two gratings are pulled by lambda / 2, so that the performance of the DFB is improved. According to the design, the side mode rejection ratio (SMSR) of laser beams can be effectively improved, the laser line width is compressed, a guarantee is provided for stable work of the laser in a high-performance application scene, and the grating reflection efficiency is effectively improved by combining a'mouth-to-mouth 'coupling butt joint mode of the gain chip and the optical waveguide substrate.

The invention relates to the technical field of lasers, in particular to a temperature self-adjusting method and device for a DFB laser with a TEC, and the method comprises the steps: collecting the temperature of the DFB laser at each moment, and the voltage and current of a TEC circuit at each moment; determining a proportional gain compensation item of the PID controller in each parameter adjustment period; analyzing the difference between the temperature change trend of the DFB laser in the local time period in each parameter adjustment period and the overall temperature change trend, and determining an integral gain compensation item of a PID controller in each parameter adjustment period; based on the fluctuation of the instantaneous frequency of the voltage and the current in the TEC circuit in each parameter adjustment period, obtaining a differential gain compensation item of a PID controller in each parameter adjustment period; and adjusting parameters of the PID controller are respectively corrected by using the proportional gain compensation item, the integral gain compensation item and the differential gain compensation item so as to adjust the temperature of the DFB laser. Therefore, the stability of temperature adjustment of the DFB laser is improved.

The invention relates to the technical field of semiconductor lasers, in particular to an external cavity laser for realizing narrow linewidth through phase difference regulation and control of a bimetallic Bragg grating, which comprises a gain chip, a first high-reflection (HR) film is plated on the left end surface of the gain chip, and a first anti-reflection (AR) film is plated on the right end surface of the gain chip; a metal Bragg grating waveguide is arranged on the right side of the gain chip, an annular resonance optical waveguide is arranged on the front side of the ridge optical waveguide, the right end face of the gain chip and the left end face of the metal Bragg grating waveguide are aligned and attached to form an outer cavity structure, and the left end face of the metal Bragg grating waveguide is plated with a second anti-reflection AR film. The right end face of the metal Bragg grating waveguide is plated with a third anti-reflection AR film. Tests show that the side mode rejection ratio (SMSR) is increased to 65dB and the line width is compressed to 0.6 kHz by using an interference enhancement effect and a mode suppression mechanism.

A semiconductor optical amplifier array device includes: a substrate; and a plurality of semiconductor optical amplifiers formed on the substrate, each of the semiconductor optical amplifiers including an active region, and two input-output ports optically connected to the active region and disposed on same facet of the semiconductor optical amplifier array device. The plurality of semiconductor optical amplifiers include a first semiconductor optical amplifier in which length of the active region is equal to a first length, and a second semiconductor optical amplifier in which length of the active region is equal to a second length that is different from the first length.

The invention discloses a preparation method and structure of a photon integrated laser, and the method comprises the steps: dividing a device into seven functional regions, including two modulator regions, two gain regions, two front grating regions and a common rear grating region; an active material of a modulator region and a passive material of a grating region are respectively formed through two times of butt-joint growth; after sampling gratings are manufactured in the front grating area and the rear grating area, a cladding layer, a contact layer and a ridge waveguide structure grow, cantilever beam heat insulation structures are formed on the two sides of the ridge waveguide of the shared grating area, and finally electrodes of the rear functional areas are manufactured. Wavelength tuning of the two lasers is achieved by sharing the rear grating area, and the size of the lasers is effectively reduced; the cantilever beam structure of the rear grating area is utilized to effectively reduce heat conduction, improve wavelength tuning efficiency and reduce power consumption; through the double-end integrated electro-absorption modulator, bidirectional light emission of a single integrated chip is realized, signal modulation of different bidirectional light emission wavelengths can be carried out, and the utilization rate of optical fiber transmission is improved.

Higher modulation speed is achieved for a laser device comprising: an active layer structure between a semiconductor substrate and a grating structure configured for manipulation, comprising a common active layer for generation of laser light; a first facet spatially adjacent to one end of and a second facet spatially adjacent to an opposing end of the active layer structure, the first facet emitting laser light, the second facet being opposite the first, both comprising anti-reflection coating; the grating structure comprising spatially adjacent integral grating sections; a cladding structure for optically confining the laser light and adapted for arranging the grating structure between the active layer and the cladding structure; a DFB structure having a first grating section, at least one DBR structure having a second grating section, the first and second grating sections sharing the common active layer for at least the integral grating sections; the DFB structure comprising a first optical function as lasing function and the at least one DBR structure comprising a second one as optical feedback.

The invention provides a topological posture single photon source device and a quantum light source, and relates to the technical field of topological quantum light sources. The topological state single photon source device comprises a GaAs layer; the SiO2 / Au structure comprises a SiO2 layer and an Au layer, and is positioned below the GaAs layer to serve as a reflecting mirror for inhibiting backward photon leakage; the topological state microcavity is processed and formed on the GaAs layer; and the quantum dots grow in the GaAs layer and are coupled with the topological posture of the topological posture microcavity to generate a topological posture single photon source. According to the invention, the coupling efficiency of the quantum dots and the microcavity is effectively improved by using the mode volume with a relatively large topological posture, the bottleneck that the coupling probability is low due to the limited volume of a traditional mode is broken through, and a better scheme is provided for realizing the interaction of high-efficiency light and substances.

A semiconductor laser (1) comprising a semiconductor body (2) with an active region (20) for generating radiation (8) and an optical interaction structure (3) with structural elements (30) is specified, wherein at least some of the structural elements (30) are arranged at different nominal center distances (35) to each other such that, during operation of the semiconductor laser (1) at a given operating point, local temperature differences in the optical interaction structure (3) reduce differences between the optical path lengths (39) that are assigned to the nominal center distances (35) of these structural elements (30). Furthermore, a method for manufacturing a semiconductor laser (1) is described.

An FM LIDAR system is described that includes a frequency modulated LIDAR system that incorporates a laser source that is optically coupled to a whispering gallery mode optical resonator. Light from the laser that is coupled into the whispering gallery mode optical resonator is coupled back out as a returning counterpropagating wave having a frequency characteristic of a whispering gallery mode of the optical resonator. This returning wave is used to reduce the linewidth of the source laser by optical injection. Modulation of the optical properties of the whispering gallery mode optical resonator results in modulation of the frequency of the frequencies supported by whispering gallery modes of the resonator, and provides a method for producing highly linear and reproducible optical chirps that are highly suited for use in a LIDAR system. Methods of using such an FM LIDAR system and vehicle assisting systems that incorporate such FM LIDAR systems are also described.

The invention discloses a wavelength thermal tuning photon integrated device and a preparation method thereof.The device comprises a substrate, a modulator layer, a front sampling grating layer, a gain layer, a rear sampling grating layer, a cover layer and an electric contact layer, the cover layer and the electric contact layer jointly form a shallow ridge waveguide structure, and the shallow ridge waveguide structure is transversely arranged in the center of the upper portion of each functional layer; the whole cover layer and the electric contact layer are etched according to a preset ridge-shaped strip pattern, a cantilever beam structure is transversely arranged in the post-sampling grating layer, the cantilever beam structure comprises a cantilever beam and air grooves in the two sides of the cantilever beam, and the cantilever beam is located under the shallow ridge waveguide structure; the cantilever beam structure is formed by etching the rear sampling grating layer below the shallow ridge waveguide structure according to a preset cantilever strip pattern; according to the technical scheme, wavelength thermal tuning is achieved through collaborative design of the shallow ridge waveguide structure and the cantilever beam grating structure, limitation of material carrier concentration is avoided, thermal response is fast, and power consumption is remarkably reduced.

A system and method for making small form ice units is provided. More specifically, a novel and advantageous system and method for converting a large form ice unit into smaller form ice units is provided. Even more specifically, a novel and advantageous system and method for forming an ice sheet and for dividing an ice sheet into a plurality of elongated segments, such as ice rods, and the elongated segments into a plurality of small form ice units, such as ice cubes is provided. The system may include a formation module for forming a large form ice structure and a converting station for converting the large form ice structure to small form ice units.

A photonic integrated circuit device includes a lasing cavity for resonating at a plurality of discrete wavelengths and an optical feedback cavity operably coupled to the lasing cavity via a front surface of the lasing cavity. The optical feedback cavity has a reflective element for reflecting light, at least partially, back into the lasing cavity to form a resonant Fabry-Perot cavity between the front surface and the reflective element. The optical feedback cavity includes a variable phase shifting element adapted for receiving an input signal to control a phase shift of light propagating in the optical feedback cavity. The amount of light entering the lasing cavity from the optical feedback cavity is low enough to avoid dynamic instability of the lasing cavity. The reduction in light is obtained using an attenuator.

The invention provides a semiconductor laser and a preparation method thereof. The preparation method comprises the following steps: forming a lower limiting layer on one side of a semiconductor substrate layer along a first direction; a ridge-shaped structure is formed on the side, away from the semiconductor substrate layer, of a part of the lower limiting layer, the ridge-shaped structure comprises a lower waveguide layer, an active layer, an upper waveguide layer, a grating layer and a cover layer which are sequentially stacked in the first direction, and the cover layer is located on the side, away from the upper waveguide layer, of the grating layer; an insulating epitaxial layer is formed on the side, away from the semiconductor substrate layer, of the lower limiting layer, the insulating epitaxial layer is located on the side, away from the semiconductor substrate layer, of the ridge-shaped structure and on the two sides, in the slow axis direction, of the ridge-shaped structure, and the thermal conductivity of the insulating epitaxial layer is larger than that of the active layer; an opening is formed in the insulating epitaxial layer, the opening exposes the cover layer, and the size of the opening in the slow axis direction is larger than that of the ridge-shaped structure in the slow axis direction; an upper confinement layer is formed in the opening.

The invention belongs to the field of lasers, and discloses a growth method for reducing laser Ith through N grating burying, which subversively adopts an N-type grating structure, uses a built-in P-N junction formed by the N-type grating structure and a subsequent P-type buried layer as a natural and efficient current blocking layer, and structurally eliminates a current leakage path. Afterwards, in the heating stage, trace arsine is introduced to carry out atomic-scale protection on the sensitive grating morphology, at the optimal mass transport temperature, the high mobility characteristic of indium atoms is utilized to carry out shape-preserving filling on grating grooves, flawless preliminary planarization is achieved, and through variable-temperature thickening growth and high-temperature annealing in the pure phosphorus atmosphere, the high-temperature-resistant grating is obtained. And performing quality optimization and defect repair on the buried layer and the key interface. The series of linked steps ensure that the indium phosphide buried layer with flat atomic scale and complete crystal lattice can grow on the fragile N-type grating, and ensure that a high-quality covering layer and an active region grow on the N-type grating.

The invention relates to a multi-path high-stability narrow-linewidth external cavity semiconductor laser and application thereof, and belongs to the technical field of lasers. The laser comprises two groups of external cavity light paths, Z-block beam combiners, partial reflectors and isolators, the two groups of external cavity light paths are arranged side by side, and the Z-block beam combiners, the partial reflectors and the isolators are sequentially arranged on the light emitting sides of the two groups of external cavity light paths; the external cavity optical path comprises a gain chip, a collimating lens, a polarization analyzer A, a polarization beam splitter, an F-P etalon and a narrow-band-pass filter which are sequentially arranged along the optical path. The polarization analyzer and the polarization beam splitter are arranged in the external cavity light path, main polarized light is kept to resonate in the external cavity light path, the polarization suppression ratio of the external cavity light path is improved, non-dominant mode noise is suppressed, and the line width is reduced; the mode jump risk is reduced, the device life is prolonged, and the power stability is improved; the beam quality is improved; and the polarization dependent loss in a light path is reduced.

The invention discloses a wavelength-tunable high-speed EML laser which comprises a substrate and four functional areas which are arranged on the substrate and are connected in sequence, wherein the four functional areas include an electric absorption modulation area (EAM), a gain area, a phase regulation and control area and a distributed Bragg reflection area (DBR). Wherein the P / N type electrodes of the functional areas are uniformly distributed on the same main surface of the chip to form a coplanar electrode structure; according to the laser, a coplanar P / N electrode structure is adopted, an EAM area, a gain area, a phase regulation and control area and a DBR area are integrated, the refractive indexes of the phase regulation and control area and the DBR area are jointly regulated and controlled through current injection, fast-response wide-range wavelength tuning is achieved, all the electrodes are evenly distributed on the same main surface of a chip, stray capacitance is remarkably reduced, high-frequency modulation performance is improved, and the laser is suitable for wide-range wavelength tuning. The device grows based on the semi-insulating InP substrate, so that the electrical isolation is enhanced, the transverse electric leakage and the crosstalk between the function intervals are effectively inhibited, and the integration consistency and stability are improved.

Systems and methods are provided for refractive index engineering for brightness enhancement and kink suppression in optical emitter devices. An example optical emitter device may include a first region that includes a first semiconductor material, an active region located on the first region, with the active region including a pumped active region between a front end and a back end of the optical emitter device, and a plurality of loss structures arranged along at least a portion of at least one side of the pumped active region. The plurality of loss structures may be arranged between the front end and the back end of the optical emitter device. The plurality of loss structures may include two or more continuous etched lines. The plurality of loss structures may include two or more discontinuous etched features.

Provided are a silicon-based tunable filter, laser and an optical module. The tunable laser comprises a semiconductor optical amplifier and a silicon photonic integrated chip, wherein a first coupler, a phase regulator and a tunable filter are provided on the silicon photonic integrated chip; the tunable filter comprises a flat-top band-pass filter structure, a Mach-Zehnder interferometry (MZI) structure and a micro ring resonation (MRR) structure, which are cascaded; gain light emitted by the semiconductor optical amplifier is coupled to the silicon photonic integrated chip by means of the first coupler, and a narrowband filtered optical signal is output by means of the tunable filter; and the phase of the gain light is regulated by means of the phase regulator so as to output single-peak narrowband laser light with a tunable target wavelength.

The invention provides a multi-junction cascade photonic crystal surface emitting laser and a preparation method thereof. The multi-junction cascade photonic crystal surface emitting laser comprises a substrate; the three-dimensional photonic crystal structure is arranged on the substrate, the three-dimensional photonic crystal structure comprises a longitudinal periodic structure formed by a plurality of laminated structures which are sequentially stacked in the vertical direction of the substrate, each laminated structure comprises an active layer and a photonic crystal layer, and the photonic crystal layer provides optical feedback for the active layer to form optical resonance; a transverse periodic structure is formed in each photonic crystal layer; and the plurality of tunnel junctions are arranged between the two adjacent laminated structures and are used for electrically connecting the two adjacent laminated structures.

The invention relates to a semiconductor laser arrangement with a laser-active material comprising layers of different semiconductor materials. A first and a second reflective element are arranged between the laser-active material, the second element being configured for extracting laser light from the laser-active material. According to the invention, at least one of the first and second elements has a layer stack with an electro-optic layer sequence. The electro-optic layer sequence comprises a first conductive and, in particular, transparent layer with a terminal; a second conductive and, in particular, transparent layer with a terminal; and an intermediate, in particular, insulating layer in which an optical parameter can be varied depending on a voltage between the first and the second layer.