Abstract: A tunable external cavity laser with dual gain chips, including: a polarization beam splitter having a beam splitting surface arranged at an angle of 45° with respect to a first direction and a second direction perpendicular to the first direction; a first gain chip arranged in the first direction; a second gain chip arranged in the second direction; a feedback cavity arranged in the first direction, wherein the feedback cavity and the first gain chip are respectively arranged on two opposite sides of the polarization beam splitter, and the feedback cavity includes at least one independent Fabry-Perot etalon, at least one air gap Fabry-Perot cavity and a mirror that are arranged in the first direction. The polarization beam splitter and the two gain chips cooperate to share the feedback cavity, so that a wavelength and a phase may be adjusted, and a larger tuning range may be obtained.

Abstract: Provided are a function switchable random access memory, including: two electromagnetic portions configured to connect a current; a magnetic recording portion between the two electromagnetic portions and including a spin-orbit coupling layer and a magnetic tunnel junction; a pinning region between each of the electromagnetic portions and the magnetic recording portion; a cut-off region on a side of each of the electromagnetic portions opposite to the pinning region, the spin-orbit coupling layer is configured to generate a spin current under an action of the current; the two electromagnetic portions is configured to generate two magnetic domains with magnetization pointing in opposite directions under an action of the spin current; the magnetic tunnel junction is configured to generate a magnetic domain wall based on the two opposite magnetic domains and is configured to drive the magnetic domain wall to reciprocate under the action of the spin current.

Abstract: Disclosed is a microwave photonic Ising machine, including: a closed loop including a phase and electro-optical conversion module and a storage, correlation and photoelectric conversion module connected in turn; a laser light source configured to generate and input an optical signal to the phase and electro-optical conversion module; and a microwave pulse local oscillator source configured to generate and input a microwave pulse signal to the phase and electro-optical conversion module. The phase and electro-optical conversion module is configured to modulate the microwave pulse signal, the optical signal, and a phase-specific two-phase microwave pulse spin electrical signal input from the storage, correlation and photoelectric conversion module to obtain and input a phase-specific two-phase microwave pulse spin optical signal to the storage, correlation and photoelectric conversion module for storage and correlation.

Abstract: A mixer-based microwave signal generation device is provided, and the mixer-based microwave signal generation device includes a microwave local oscillator source, a mixer, a first filter, a laser, an electro-optic modulator, an optical signal delayer, a photodetector, a second filter, an amplifier and a passive power divider.

Abstract: A laser cleaning method and device for improving uniformity of a laser cleaning surface are provided. The laser cleaning method includes: applying a peaked-top sine wave signal to a motor; controlling a galvanometer to swing in a reciprocated manner by the motor; shaping a laser beam emitted by a laser to a linear beam by the reciprocated swing of the galvanometer; and performing laser cleaning using the shaped linear beam.

Abstract: A broadband tuning system includes a first chip and a second chip. The first chip includes a first light amplification region, a first forward grating region and a first backward grating region that are sequentially arranged in a first direction. The first light amplification region is configured to amplify a first light source and to turn on or turn off the first light source, and the first forward grating region and the first backward grating region are configured to tune the first light source. The second chip includes a second light amplification region, a second forward grating region and a second backward grating region that are sequentially arranged in a second direction. The second light amplification region is configured to amplify a second light source and to turn on or turn off the second light source, and the second forward grating region and the second backward grating region are configured to tune the second light source.

Abstract: A photonic chip and a preparation method thereof are provided. The chip includes a lithium niobate film modulator array, a first optical coupling array, and a silica waveguide wavelength-division multiplexer, and the lithium niobate film modulator array includes one or more lithium niobate film modulators and is used to modulate an optical signal; the first optical coupling array includes one or more first optical coupling structures, and the first optical coupling structure has one end connected to a corresponding lithium niobate thin film modulator and the other end connected to the silica waveguide wavelength-division multiplexer so as to transmit the modulated optical signal to the silica waveguide wavelength-division multiplexer; and the silica waveguide wavelength-division multiplexer is used to perform wavelength-division multiplexing on the modulated optical signal.

Abstract: An acousto-optic Q switch, a resonant cavity, and a pulse laser device for improving laser device power. The acousto-optic Q switch includes: a transparent optical element configured to form a phase grating that diffracts laser; a piezoelectric transducer arranged at one end of the transparent optical element and configured to convert electrical energy into ultrasonic energy to form the phase grating in the transparent optical element; and an absorber arranged at the other end of the transparent optical element to absorb the ultrasonic energy.

Abstract: A method for fabricating a semiconductor structure having an enhanced hole linear Rashba spin-orbit coupling effect includes: providing a substrate; and growing a germanium quantum well on the substrate. A silicon atomic layer is inserted at an interface between a well and a barrier of the germanium quantum well. The silicon atomic layer includes one or more monolayers.

Abstract: A fabrication method for a semiconductor structure with a hole spin qubit includes: providing a substrate; growing a germanium quantum well on the substrate, in which the germanium quantum well is an inclined quantum well structure grown in a [110] direction, and the germanium quantum well is grown by a complementary metal oxide semiconductor process; and fabricating a two-dimensional gate-defined quantum dot in the germanium quantum well.

Abstract: A frequency spectrum detection system including: a frequency-scan light source, a phase modulator, an optical filter, an optical fiber, a photodetector, a power divider, an electric amplifier, a combiner, an electric filter, and an oscilloscope. The frequency-scan light source, the phase modulator, the optical filter, the photodetector, and the electric amplifier form a ring-shaped optoelectronic oscillator resonant cavity, which is configured to generate a frequency-scan signal. The combiner is configured to receive a signal to be measured. The phase modulator is configured to modulate the combined electrical signal onto a frequency-scan optical signal. The optical filter is configured to selectively attenuate or amplify one sideband of double sidebands of the double-sideband phase-modulated optical signal. The photodetector is configured to detect a signal filtered by the optical filter.

Abstract: A Fourier domain mode-locked optoelectronic oscillator includes a laser light source, a phase modulator, an optical notch filter, a photodetector, an electrical amplifier and a power divider; wherein the laser light source, the phase modulator, the optical notch filter and the photodetector together form a swept microwave photonic filter. The passband of the swept microwave photonic filter is determined by the difference in wavelength corresponding to the laser light source and the notch positions of the optical notch filter. In the present disclosure, the laser light source, the phase modulator, the optical notch filter, and the photodetector are configured to form a fast swept microwave photonic filter, the sweeping of a passband of the microwave photonic filter is realized by the sweeping of the laser light source or the optical notch filter, and the change in the filter's passband is matched with the latency for delivering a signal in the optoelectronic oscillator loop for one trip.

Abstract: A method and a system for optimizing problem-solving based on probabilistic bit circuits are provided. The method includes: performing a modeling transformation on an objective problem to obtain a corresponding Hamiltonian relationship; obtaining a column Hamiltonian of said probabilistic bit circuit based on said Hamiltonian relationship; and performing parallel annealing iterations on multicolumn Hamiltonian based on row-flipping operations on said probabilistic bit circuits to obtain an updated probabilistic bit configuration, so as to achieve optimization of said problem.

Abstract: An optical coupling structure, an optical coupling system and a method for preparing the optical coupling structure are provided. The method includes: step S101: preparing a base substrate; step S102: forming a lithium niobate optical waveguide on the base substrate; step S103: forming a silicon dioxide core layer enclosing the lithium niobate optical waveguide on peripheral walls of the lithium niobate optical waveguide; step S104: forming a silicon dioxide cladding layer enclosing the silicon dioxide core layer on peripheral walls of the silicon dioxide core layer. The optical coupling structure alleviates a technical problem of low coupling efficiency between the lithium niobate optical waveguide and the single-mode optical fiber in the related art, and achieves a technical effect of improving the coupling efficiency between the lithium niobate optical waveguide and the single-mode optical fiber.

Abstract: An on-chip integrated semiconductor laser structure and a method for preparing the same. The structure includes: an epitaxial structure including a first N contact layer, a first N confinement layer, a first active region, a first P confinement layer, a first P contact layer, an isolation layer, a second N contact layer, a second N confinement layer, a second active region, a second P confinement layer, and a second P contact layer sequentially deposited on a substrate; a first waveguide and a second waveguide; a first optical grating and a second optical grating; and current injection windows.

Abstract: An integrated Fourier domain mode-locked optoelectronic oscillator and its application and a communication system are provided, which relates to the technical field of microwave photonics. The integrated Fourier domain mode-locked optoelectronic oscillator includes an optoelectronic chip and an electronic chip. The optoelectronic chip includes a laser, a modulator, an optical notch filter, and a photodetector coupled via an optical waveguide. The electronic chip includes an electrical amplifier and a power splitter coupled via a coplanar microwave waveguide. The volume, weight and power consumption of the Fourier domain mode-locked optoelectronic oscillator is greatly reduced by integrating all the devices on the chip. A tunable sweeping microwave signal output is realized, and the sweeping speed of the output signal is increased. The integrated Fourier domain mode-locked optoelectronic oscillator can be used in radars and communication systems.

Abstract: The present disclosure provides a tunable broadband random optoelectronic oscillator, including: a laser light source configured to generate continuous laser light; a positive feedback loop formed by an intensity modulator, an optical circulator, an optical filter, an optical amplifier, a photodetector, an electric filter and an electric amplifier connected in sequence, wherein the positive feedback loop is configured to receive the continuous laser light to generate a microwave signal and achieve an optic-electro/electro-optic conversion; a Raman laser configured to generate Raman pump light; a wavelength division multiplexer having a first input terminal connected to the Raman laser and a second input terminal connected to the optical circulator; and a dispersion compensation fiber connected to an output terminal of the wavelength division multiplexer; wherein forward transmission laser light passing through the optical circulator and the Raman pump light are coupled into the dispersion compensation fiber t

Abstract: A laser cleaning system including a laser source, an energy-transferring optical fiber, a laser cleaning head, a coreless motor, a connection lens barrel, and a mirror.

Abstract: Exemplary embodiments of the present disclosure provide a spin valve and a spintronic device comprising the same. The spin valve may comprise two or more magnetic layers stacked in sequence, wherein the spin valve further comprises at least one pair of nonmagnetic semiconductor layers arranged between any two adjacent magnetic layers among the two or more magnetic layers, wherein a built-in electric field is formed between the at least one pair of nonmagnetic semiconductor layers.

Abstract: A GaN-based VCSEL chip based on porous DBR and a manufacturing method of the same, wherein the chip includes: a substrate; a buffer layer formed on the substrate; a bottom porous DBR layer formed on the buffer layer; an n-type doped GaN layer formed on the bottom porous DBR layer, which is etched downward on its periphery to form a mesa; an active layer formed on the n-type doped GaN layer; an electron blocking layer formed on the active layer; a p-type doped GaN layer formed on the electron blocking layer; a current limiting layer formed on the p-type doped GaN layer with a current window formed at a center thereof, wherein the current limiting layer covers sidewalls of the active layer, the electron blocking layer and the convex portion of the n-type doped GaN layer; a transparent electrode formed on the p-type doped GaN layer; an n-electrode formed on the mesa of the n-type doped GaN layer; a p-electrode formed on the transparent electrode with a recess formed therein; and a dielectric DBR layer formed on