A simple analysis is presented of twin-stripe semiconductor Y-junction laser amplifier switches that operate through simultaneous changes in gain and refractive index due to free carrier injection. This shows that (in contrast to four-port directional coupler devices based on the same mechnism) good cross-talk performance may be obtained for a wide range of operating conditions.

Aimed at the safety problem of the locomotive under the dynamic braking condition, analysis the influence of the coupler and buffer system. The coupler reposition methods of the large rotation angle coupler and the small rotation angle coupler under longitudinal coupler press force was compared. The influence of coupler and buffer system to the dynamics performance of locomotive was researched ...

This work presents the design of a compact dual-port circularly polarized antenna based on new coupler topology. The can radiate right-hand circular polarization (RHCP) in two opposite directions depending input port. In proposed structure, radiating system has three inverted F antennas connected to 120∘ hybrid coupler. modeling and 5-ports are described experimentally validated. prototype is f...

The aided threshold (and functional gain) has been used as a behavioral verification tool since the early 1960s to document the improvement in hearing sensitivity with hearing aid use. Clinicians judge the adequacy of amplification by examining if the aided threshold reaches a prescribed target value. The functional gain provided by the hearing aids, or the difference in audiometer dial reading...

A terahertz master-oscillation power-amplifier quantum cascade laser (THz-MOPA-QCL) is demonstrated where a grating coupler is employed to efficiently extract the THz radiation. By maximizing the group velocity and eliminating the scattering of THz wave in the grating coupler, the residue reflectivity is reduced down to the order of 10-3. A buried DFB grating and a tapered preamplifier are prop...

Custom in-the-ear (ITE) hearing aids (standard linear amplifiers with single-pole-filter low-frequency tone control and a class A amplifier output stage) were fit to 90 ears using the revised National Acoustics Laboratories' formula (NAL-R), and to 20 ears each using Prescription of Gain/Output II (POGO II) and Memphis State University (MSU) formulas. Both real-ear insertion gain and 2-cc coupl...

Linear and nonlinear gain characterization of electrically pumped vertical external cavity surface emitting lasers (EP-VECSELs) is presented with spectrally resolved measurements of the gain and with gain saturation measurements of two EP-VECSEL samples with different field enhancement in the quantum-well gain layers. The spectral bandwidth, small-signal gain and saturation fluence of the devic...

In this paper sensitivity analysis of a wideband backward-wave directional coupler due to fabrication imperfections is done using Monte Carlo method. For using this method, a random stochastic process with Gaussian distribution by 0 average and 0.1 standard deviation is added to the different geometrical parameters of the coupler and the frequency response of the coupler is estimated. The appli...

This study presents the design and analysis of a 180° tunable non-reciprocal active broadband coupler. To increase bandwidth, multi-section impedance transformation technique is utilised. The coupler includes two amplifiers, three filters (phase-shifters) on gate (drain) line, referred to as through-path (coupled-path). achieve an accurate coupler, staggering utilised for designing filters. Lum...

we propose a new ring resonator side-coupled m-z interferometer all-optical switch throughthe pumped nonlinear directional coupler. by controlling pump power p to lead the coupler reflectivityr approaching to 1, the resonator finesse will be enhanced dramatically, and then the minimumswitching power in silica-based practice devices can be obtained. as a sample, we use a nonlinearcoupler made by...