Abstract: A mid-infrared semiconductor saturable absorber mirror based on InAs/GaSb superlattice comprises a GaSb substrate with an anti-reflection film coated on the lower surface of the GaSb substrate; InAs/GaSb superlattice which has a specific structure and thickness and is arranged on the GaSb substrate; and Bragg reflection film which is arranged on the InAs/GaSb superlattice, wherein Bragg reflection film is composed of multiple pairs of ZnS and YbF3 film layers with a thickness of ¼ wavelength, and the YbF3 film layer is connected with the InAs/GaSb superlattice. The device not only has a mid-infrared working range with a broadband operation bandwidth, but also has the advantages of designable parameters, outstanding robustness, high damage threshold and the like, and sets a foundation for the development of mid-infrared ultrafast mode-locked lasers.

Abstract: It is an object of the present invention to provide a production method of a calcium-based metallic glass alloy molded body for medical use which has a biodegradable property, has a mechanical strength equal to or higher than that of metal materials, and enables complex molding and a wide range of applications. The calcium-based metallic glass alloy molded body for medical use is produced by mixing a metal powder including a calcium powder, alloying the mixed metal powder, and sintering the alloyed mixed metal powder.

Abstract: Ultrafast group-velocity control method and device thereof comprising a signal path successively comprising a seed laser source, a pulse stretcher, and a first pulse compressor; a pump path comprising a pump laser source; an amplifier comprising a nonlinear crystal with chirped poled-period; and an idler path successively comprising a spectral filter and a second pulse compressor after amplifier. Both chirped signal pulse from the pulse stretcher and pump pulse from the pump source incident into the amplifier, where energy continuously transfers from the pump pulse to the chirped signal pulse and a newly generated idler pulse. The amplified chirped signal pulse is directly compressed by first pulse compressor and the generated idler pulse is firstly filtered by the spectral filter and then compressed by the second pulse compressor. After amplification and compression, both signal and idler are delayed, and group delay is adjusted by the pump intensity.

Abstract: A high-average-power OPCPA amplifier comprising a pump laser, a signal laser, and a nonlinear crystal amplifier. The pump laser includes an Nd:YVO4 laser oscillator-regenerative amplifier, an Nd:YAG boost amplifier, a frequency-doubling convertor, and a frequency-tripling convertor. The signal laser includes a supercontinuum generator, a pulse stretcher, and a pulse compressor. The chirped signal and the pump laser is intersected with a noncollinear angle of 3.0° to 4.0° in the nonlinear crystal amplifier and the temperature of the crystal amplifier is set at higher than 320K for simultaneous temperature- and wavelength-insensitive phase-matching.

Abstract: It is an object of the present invention to provide a production method of a calcium-based metallic glass alloy molded body for medical use which has a biodegradable property, has a mechanical strength equal to or higher than that of metal materials, and enables complex molding and a wide range of applications. The calcium-based metallic glass alloy molded body for medical use is produced by mixing a metal powder including a calcium powder, alloying the mixed metal powder, and sintering the alloyed mixed metal powder.

Abstract: A method for generating femtosecond vortex beams with high spatial intensity contrast, where a noncollinearly pumped HG beam femtosecond laser generates femtosecond HG beam and a cylindrical lens mode converter converts the femtosecond HG beam to femtosecond LG vortex beam. The HG beam femtosecond laser comprises a pump source, a gain medium, a saturable absorption mirror as mode-locker, and an output coupler with a noncollinear angle between the laser beam and the pump beam in the gain medium, which enables the laser to generate pure, order-tunable femtosecond HG beams. Femtosecond vortex beams obtained after the cylindrical lens converter have high-intensity-contrast, and are topological charge-tunable.

Abstract: A method for generating femtosecond vortex beams with high spatial intensity contrast, where a noncollinearly pumped HG beam femtosecond laser generates femtosecond HG beam and a cylindrical lens mode converter converts the femtosecond HG beam to femtosecond LG vortex beam. The HG beam femtosecond laser comprises a pump source, a gain medium, a saturable absorption mirror as mode-locker, and an output coupler with a noncollinear angle between the laser beam and the pump beam in the gain medium, which enables the laser to generate pure, order-tunable femtosecond HG beams. Femtosecond vortex beams obtained after the cylindrical lens converter have high-intensity-contrast, and are topological charge-tunable.

Abstract: A simultaneous temperature- and wavelength-insensitive parametric amplifier comprising a pump laser, a signal laser, and a crystal amplifier. The pump laser system on a first optical pathway includes a Nd:YVO4 laser oscillator-regenerative amplifier and a Nd:YAG boost amplifier. The pump laser beam is generated from the pump laser system, passes through the first image-relay system, and is frequency-doubled in the frequency-doubling crystal. The signal laser system on a second optical pathway comprises a Ti:sapphire regenerative amplifier and generates the signal laser beam, which passes through the pulse stretcher and is temporally chirped and imposed with an angular dispersion by the first grating. The chirped signal beam and pump laser beam are intersected with a noncollinear angle of >5° in the crystal amplifier for temperature-insensitive phase-matching (PM).

Abstract: A novel-structure electromagnetic relay containing a permanent magnet. At least three pairs of leading-out rods penetrate through a rectangular base, two pairs of leading-out rods are connected with the lower ends of four static spring plates respectively, an iron core and a coil framework are arranged at a diagonal position on the upper surface of the base, winding connectors of coils are connected with the other pair of leading-out rods respectively, the static spring plates are arranged at the other diagonal position on the upper surface of the base, a support is arranged at the top end of the coil framework, a pole face, a yoke and the permanent magnet are installed on the support, an armature, movable spring plates, the pole face and the yoke are located and connected through a middle shaft, and a sealing casing is covered outside the relay.

Abstract: Quasi-parametric chirped-pulse amplifier comprising a signal path, a pump path, and an amplifier. A dedicated nonlinear crystal doped with rare-earth-ions is used which has strong absorption around the idler waveband. Both the chirped signal pulse and the pump pulse incident into the amplifier, where energy continuously transfers from the pump pulse to the signal pulse and a newly generated idler pulse. The energy of the generated idler pulse is continually absorbed by the rare-earth ions doped in the amplifier.

Abstract: Quasi-parametric chirped-pulse amplifier comprising a signal path, a pump path, and an amplifier. A dedicated nonlinear crystal doped with rare-earth-ions is used which has strong absorption around the idler waveband. Both the chirped signal pulse and the pump pulse incident into the amplifier, where energy continuously transfers from the pump pulse to the signal pulse and a newly generated idler pulse. The energy of the generated idler pulse is continually absorbed by the rare-earth ions doped in the amplifier.

Abstract: An electromagnetic structure comprising permanent magnets comprises an outer yoke (a6), a first permanent magnet group (a3, a5), an inner yoke (a8), an armature (a1), and a second permanent magnet group (a2, a4). The outer yoke is in a hollow cylinder shape. The first permanent magnet group comprises multiple permanent magnets arrayed in a round shape, the multiple permanent magnets are connected to the outer yoke, and a magnetizing direction of each permanent magnet is along an axial direction. The inner yoke comprises an inner yoke upper base, an inner yoke sidewall, and an inner yoke lower base. The inner yoke upper base and the inner yoke lower base are separately extended outwards and horizontally from an upper end and a lower end of the inner yoke sidewall to form a circular ring. The armature comprises an armature upper base, an armature lower base, and an armature barrel body.

Abstract: A spatiotemporally resolved far-field pulse contrast measuring device includes a plano-convex cylindrical lens, a nonlinear correlation crystal, a plano-convex imaging lens and a signal-receiving system. The signal-receiving system includes a fiber array, a photomultiplier and a digital oscilloscope.

Abstract: An electromagnetic structure comprising permanent magnets comprises an outer yoke (a6), a first permanent magnet group (a3, a5), an inner yoke (a8), an armature (a1), and a second permanent magnet group (a2, a4). The outer yoke is in a hollow cylinder shape. The first permanent magnet group comprises multiple permanent magnets arrayed in a round shape, the multiple permanent magnets are connected to the outer yoke, and a magnetizing direction of each permanent magnet is along an axial direction. The inner yoke comprises an inner yoke upper base, an inner yoke sidewall, and an inner yoke lower base. The inner yoke upper base and the inner yoke lower base are separately extended outwards and horizontally from an upper end and a lower end of the inner yoke sidewall to form a circular ring. The armature comprises an armature upper base, an armature lower base, and an armature barrel body.

Abstract: A method for generating ultrashort femtosecond pulses in the optical parametric oscillator pumped by long pulses, comprising governing dispersion and nonlinearity in the optical parametric oscillator, forming linearly-chirped long pulses with broad bandwidth in the optical parametric oscillator, compressing the linearly-chirped long pulses to femtosecond pulses by a second-order dispersion outside the optical parametric oscillator cavity. The ultrashort femtosecond pulse is generated in the OPO with long pulse pumping.

Abstract: A method for generating ultrashort femtosecond pulses in the optical parametric oscillator pumped by long pulses, comprising governing dispersion and nonlinearity in the optical parametric oscillator, forming linearly-chirped long pulses with broad bandwidth in the optical parametric oscillator, compressing the linearly-chirped long pulses to femtosecond pulses by a second-order dispersion outside the optical parametric oscillator cavity. The ultrashort femtosecond pulse is generated in the OPO with long pulse pumping.

Abstract: A spatiotemporally resolved far-field pulse contrast measuring device includes a plano-convex cylindrical lens, a nonlinear correlation crystal, a plano-convex imaging lens and a signal-receiving system. The signal-receiving system includes a fiber array, a photomultiplier and a digital oscilloscope.

Abstract: A method for filtering noises in an optical parametric chirped-pulse amplifier by a spatial-chirp-dressed seed beam is provided. The various noises that grow during amplification course, including parametric super-fluorescence, pump distortion-induced noise and surface-reflection-initiated pre-pulses, will not have the spatial and temporal chirp. After dechirping amplified signal with a compressor, a main pulse having its spatial and temporal chirp removed completely is produced, while the noises acquire an additional spatiotemporal coupling, making themselves highly distinguishable from signal in space, and hence supporting noise filtering effectively and expediently in spatial domain that would not be possible otherwise. The method has capabilities of an order of magnitude reduction in noise energy and several orders of magnitude enhancement in temporal contrast.

Abstract: A novel-structure electromagnetic relay containing a permanent magnet. At least three pairs of leading-out rods penetrate through a rectangular base, two pairs of leading-out rods are connected with the lower ends of four static spring plates respectively, an iron core and a coil framework are arranged at a diagonal position on the upper surface of the base, winding connectors of coils are connected with the other pair of leading-out rods respectively, the static spring plates are arranged at the other diagonal position on the upper surface of the base, a support is arranged at the top end of the coil framework, a pole face, a yoke and the permanent magnet are installed on the support, an armature, movable spring plates, the pole face and the yoke are located and connected through a middle shaft, and a sealing casing is covered outside the relay.

Abstract: A method for filtering noises in an optical parametric chirped-pulse amplifier by a spatial-chirp-dressed seed beam is provided. The various noises that grow during amplification course, including parametric super-fluorescence, pump distortion-induced noise and surface-reflection-initiated pre-pulses, will not have the spatial and temporal chirp. After dechirping amplified signal with a compressor, a main pulse having its spatial and temporal chirp removed completely is produced, while the noises acquire an additional spatiotemporal coupling, making themselves highly distinguishable from signal in space, and hence supporting noise filtering effectively and expediently in spatial domain that would not be possible otherwise. The method has capabilities of an order of magnitude reduction in noise energy and several orders of magnitude enhancement in temporal contrast.