A terahertz (THz) metamaterial biosensor based on four identical resonators is experimentally demonstrated, and high sensitivity achieved by exciting synchronous inductor-capacitor oscillations in a unit cell. The effect of geometries the resonance frequency sensor investigated using finite integration time domain method, simulated 85 GHz per refractive index unit. sample fabricated surface micromachining process characterized THz spectroscopy system combined with bovine serum albumin (BSA)...

Based on the inhomogeneous T-Q relation constructed via off-diagonal Bethe Ansatz, Bethe-type eigenstates of XXZ spin-1/2 chain with arbitrary boundary fields are constructed. It is found that by employing two sets gauge transformations, proper generators and reference state for constructing vectors can be obtained respectively. Given an eigenvalue, it proven resulting eigenstate transfer matrix, provided parameters satisfy associated Ansatz equations.

Electrical current manipulation of magnetization switching through spin-orbital coupling in ferromagnetic semiconductor (Ga,Mn)As Hall bar devices has been investigated. The efficiency the current-controlled is found to be sensitive orientation with respect crystalline axes. dependence spin-orbit effective magnetic field on direction and magnitude determined from shifts angle. We find that strain induced about three times as large Rashba our GaMnAs devices.

Diatomite has been verified as an economical adsorbent to treat wastewater. Unfortunately, limited by poor regeneration and inert surface with less active silanol groups, the retrievable efficient diatomite-based needs be further explored. Here, on basis of thorough activation treatments raw diatomite, we developed a uniform assembly Fe3O4 nanoparticles surface. The nanocomposite possesses high specific area, trait magnetic separation, more functional groups for adsorption. maximum...

This paper finds the approximate analytical scattering state solutions of arbitrary 1-wave Schrödinger equation for generalized Hulthén potential by taking an improved new scheme centrifugal term. The normalized radial wave functions l-wave are presented and corresponding calculation formula phase shifts is derived. Some useful figures plotted to show accuracy obtained results two special cases standard Woods–Saxon also studied briefly.

We demonstrate a metal-stripe sampled Bragg grating distributed feedback terahertz quantum cascade laser for power scaling up along with reliable single-mode emission. The major advantage is that the effective coupling coefficient can be flexibly engineered by tuning sampling duty cycle. With technology, peak of 186 mW realized in pulsed operation at 10 K, which approximately 1.35 times uniform laser. Besides, horizontal beam pattern close to Gaussian distribution ideal quality.

We examine selective reflection (SR) spectrum of an Airy beam at interface between a dielectric and homogeneous atomic medium. It is shown that both the general (GR) SR beams exhibit accelerating dynamics with parabolic trajectory, however, rate for slightly greater than GR. Due to interaction atoms resonant atoms, can create far-field interference patterns. also show amplitude be dramatically modified by detuning incident fields, reduced x-coordinate distance from interface. The medium...

We demonstrate continuous-wave (CW) high power-efficiency terahertz quantum cascade laser based on semi-insulating surface-plasmon waveguide with epitaxial-side down (Epi-down) mounting process. The performance of the device is analyzed in detail. emits at a frequency ∼ 3.27 THz and has maximum CW operating temperature 70 K. peak output powers are 177 mW pulsed mode 149 10 K for 130-μm-wide Epi-down mounted lasers. record wall-plug efficiencies direct measurement 2.26% 2.05% mode, respectively.

We report the observation of multi-component dipole and vortex vector solitons composed eight coexisting four-wave mixing (FWM) signals in two-level atomic system. The formation stability are observed via changing experiment parameters, including frequency detuning, powers, spatial configuration involved beams temperature medium. transformation between modulated rotating is at different detunings. interaction forces components also investigated.

We experimentally demonstrate a metamaterials (MMs)-based terahertz (THz) sensor to quickly distinguish the cancer tissues from normal tissues. The MMs-based THz has two strong resonance absorption peaks at about 0.706 and 1.14 THz, respectively. When is covered with tissues, redshifts 1.14 THz are 31 19 GHz, However, if tissue attached surface of sensor, corresponding only 15 12 GHz, This study proposes new method for quick diagnosis early lung other cancers.

The phase-locking, noise, and modulation properties of two face-to-face optically mutual-injected terahertz (THz) quantum cascade lasers (QCLs) are analyzed theoretically. In the phase-locking range, THz QCLs in stationary states working at same frequency. Outside amplitude instantaneous frequency optical field oscillate with time, power spectrum shows a series discrete peaks. For strong mutual injection, QCL array also exhibits oscillatory behavior. Coherent collapse or chaotic behavior is...

We demonstrate that beams originating from Fresnel diffraction patterns are selfaccelerating in free space.In addition to accelerating and self-healing, they also exhibit parabolic deceleration property, which is stark difference other beams.We find the trajectory of paraxial similar nonparaxial Weber beams.Decelerating regions separated by a critical propagation distance, at no acceleration present.During deceleration, undergo self-smoothing, oscillations diffracted waves gradually smooth...

Carefully designed distributed feedback terahertz quantum cascade lasers based on surface metallic‐stripe grating structure are presented. Stable single‐mode emission with a side‐mode suppression ratio of >20 dB is obtained under all injection currents and operating temperatures. Maximum edge‐emitting power 58 mW realised in continuous‐wave mode. In pulsed mode, record output powers 286 at 10 K 82 77 achieved 97.1 μm well‐shaped beam pattern.

We report a low threshold power density and high output terahertz quantum cascade laser emitting at ∼3.9 THz operating in continuous-wave mode. The wall-plug efficiency are achieved based on hybrid bound-to-bound active design. A record of 312 mW 0.8 kW/mm 3 (threshold current 109 A/cm 2 ) mode 20 K is demonstrated for 300-μm-wide 2-mm-long single-ridge device. highest 1.38% the slope 684 mW/A with an internal ∼120 photons per injected electron. demonstration this low-threshold high-power...

The coefficient of selective reflection at oblique incidence from two-level atoms confined between two dielectric walls is calculated in this paper. It found to be related the transient behaviour after colliding with wall and distribution field inside vapour corresponds L/λ, L thickness film λ incident wavelength. We find that sub-Doppler structure manifest both for normal small angle incidence. feasible detect real part several cases have not been achieved before.

We study the scattering states of screened Coulomb potential in nonrelativistic frame. The explicitly calculation formula phase shift is derived and normalized radial wave functions on scale are presented. By studying analytical properties amplitude screening effects bound discussed numerically. It shown that increase with increasing parameter, especially for large quantum states.

To estimate the measurement model parameters of a three-dimensional (3D) laser scanner, spatial sphere-based calibration method by combining invasive weed optimization (IWO) and Levenberg-Marquardt (LM) algorithm is proposed in this paper. A nonlinear objective function 3D scanner established according to distance constraint between each scanning point on spherical object center sphere. reduce influence outliers, Pseudo-Huber loss also employed function. After that, hybrid IWO LM adopted...

High‐power terahertz quantum cascade lasers at −97.4 μm based on coplanar waveguide epitaxial‐side down (Epi‐down) mounting technique are presented. With the improved thermal management, excellent performance is obtained for Epi‐down mounted lasers. The maximum output powers of 685 mW in pulsed mode and 164 continuous‐wave (C‐W) realised 10 K. C‐W wall‐plug efficiency 1.67% also realised. Fundamental lateral emissions achieved wide ridge through a loss differentiation process.

High-power terahertz frequency quantum cascade lasers operating in both pulsed and continuous wave (CW) modes are demonstrated. High Al composition four wells active region based on diagonal structure employed to suppress the escape of electrons into continuum thermally activated LO-phonon scattering, as evidenced by activation energy value ~14.4 meV extracted from experimental data. The devices operate a range 3.8 - 4.05 THz have maximum temperature ~119 K. total optical output power an...

This paper presents a theoretical study of wavelength dependence four-wave-mixing (FWM) spectroscopy in micrometric thin atomic vapour. It compares three cases termed as mismatched case I, matched and II for the probe less, equal greater than pump respectively. finds that Dicke-narrowing can overcome width broadening induced by Doppler effects polarisation interference thermal atoms, high resolution FWM spectra be achieved both many cases. also magnitude signal dramatically modified to...