In this study, an optical setup for generating terahertz (THz) pulses through a two-color femtosecond laser filament was carefully designed to achieve precise overlap of in space and time. β-barium borate (BBO), α-BBO, dual-wavelength plate were used compensate the phase delay lasers. Tilting α-BBO could further realize spatial two beams by counteracting walk-off effect. The maximum output THz pulse energy reached 21 μJ argon gas when using commercial Ti:sapphire with 6 mJ at 1 kHz...

Theoretical analysis to the defect mediated discrete solitons in one- and two-dimensional periodical waveguide lattices is presented. The arrays with these functional defects are assumed respond light field as an optically induced photorefraction they patterned by a holographic technique. It found that spatial energy distributions of solitary waves can be controlled arrays, this gives rise additional freedom externally shaping distribution special shape.

The THz generation efficiency and the plasma density generated by a filament in air have been found anti-correlated when pumped <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>800</mml:mn> <mml:mtext> </mml:mtext> <mml:mtext>nm</mml:mtext> <mml:mo>+</mml:mo> <mml:mn>1600</mml:mn> </mml:math> two-color laser field. near zero delay of two pulses has minimum value, which is opposite to trend contradicts common sense. lower cannot be explained static tunneling...

Two-color femtosecond (fs) laser filamentation in the gas medium is an effective way to generate broadband and high intensity terahertz (THz) pulse. The interdigitated photoconductive antenna (iPCA) has advantages of both detection signal-to-noise ratio (SNR), which a very detect THz pulse produced by two-color fs filamentation. signal from comprehensively characterized iPCA, achieves SNR, sensitivity, polarization detection. This work provides new idea for power coherent

Abstract Jet pulse assembly is one of the main components jet hydraulic oscillator. The pressure wave characteristics produced by have an important influence on performance tool. In this paper, structure and working principle are studied, mechanical analysis model piston rod established, dynamic resistance ratio formula deduced, numerical simulation test 89-mm parameters carried out. results show that downward stroke driven both element driving force throttle plate load force, can stably...

A series of new intramolecular charge transfer compounds with absorption bands in shorter wavelengths have been synthesized. Bright visible light emits from the crystals these under infrared pulsed laser pumping. The spectral and pump density dependent properties demonstrate that some emissions are up-conversion fluorescence due to two photon absorption. fluorescent yields one- two-photon same order at high density. This work demonstrates good candidates for nonlinear optical materials.

Experimental generation of ultrashort, frequency-tunable optical pulses in liquid-core fibers is reported. Passage high-energy through a submillimeter fiber reveals quasi-linear frequency sweep. The subsequent use grating dispersion system and spectral window shortens the Nd:YAG laser pulse duration from 45 ps to less than 2 ps. Based on filtering after pair, wavelength generated short shown be tunable.

This study presents what we believe to be a novel gold-silica-gold stacked metamaterial structure based on the principle of coherent perfect absorption (CPA) realize high-contrast all-optical logic gates operating at dual communication wavelengths centered around 1310 nm and 1550 nm. By optimizing asymmetric split ring (ASR) structure, strong Fano-type plasmonic modes are achieved, leading CPA in target wavelengths. manipulating phase difference intensity incident light beams, designed can...

When the near-infrared femtosecond Bessel laser beam (fs-BLB) is obliquely incident on silica glass, annular beams (ABs) with bandwidths of several tens nanometers and different peak wavelengths discretely distributed in a visible range are generated simultaneously. It considered that four-wave mixing (FWM) corresponding cascaded parametric processes responsible for generation multi-wavelength ABs. also found broken symmetry optical setup due to oriented glass absorption band sample...

Stimulated dynamic light scattering (SDLS) in ${\mathrm{CS}}_{2}$ is studied by time-resolved pump-density-dependent experiments this paper. It found that SDLS consists of two main contributions, one which dominates at the rise time pump pulse, and other around peak high-density pulse. The former related to molecular orientation, damped intermolecular vibration, translation, while latter interactions. Our experimental results demonstrate due dipole interaction has a higher pump-power-density...

Thermal instability of a conduction channel in nonmetallic field emission regime has been assumed as an origin cathode-initiated vacuum breakdown process. In this article, details are given theoretical study thermal response insulating media to dc fields, which takes into account the effect temperature rise on from substrates. It is found that can lead regenerative process, will finally cause runaway. addition, analysis was carried out chemical vapor deposition diamond films, and it reveals...

A novel dispersion model different from the conventional one is introduced to enhance supercontinuum generation in dispersion-flattened/decreasing fiber. The results show that spectrum generated this fiber by far wider than one,whose flat width can be nearly 1000 nm. further both parameters such as peak chromatic dispersion, differential constant and decreasing coefficient pump pulse including width, soliton order, frequency chirp are crucial ultra-wideband

An analysis is carried out of the physical origin thermal instability that can trigger a catastrophic vacuum breakdown event in microelectronic devices based on flat diamond emitters. The temperature rise film will enhance internal field emission across metal–diamond interface. This effect lead to regenerative process initiate at lower than melting point an emitter. A set equations has been developed. These theoretical findings are successfully applied explain from nondoped films.

A set of coupled equations is derived and used to analyze transient coherent degenerate four-wave mixing (DFWM) in a two-level system. The numerical results show that the case near-resonance, intense pumping, short pulses, properties have interesting interaction characteristics, such as quasi-periodicity pump pulse area, probe areas, energy reflectivity, oscillatory behavior DFWM pulse, generation signal delayed incidence, where three incident pulses do not overlap medium.< <ETX...

This paper aims to solve several defects of a 122mm fluidic oscillator in practical application, namely, unstable communication, high pressure drop, and low pulse amplitude.These were solved through mechanical analysis field test.The results show that the downstroke piston rod can work smoothly, but upstroke cannot due overcurrent resistance at throttle plate.Through design optimization, plate reduce upward resistance, while increasing amplitude.Experiments indicate initial displacement new...