We consider the asymmetric active coupler (AAC) consisting of two coupled dissimilar waveguides with gain and loss. We show that under generic conditions, not restricted by parity-time symmetry, there exist finite-power, constant-intensity nonlinear supermodes (NS), resulting from the balance between gain, loss, nonlinearity, coupling and dissimilarity. The system is shown to possess non-recipr...

The Vibrant Soundbridge (VSB) with stapes clip coupler placement at the stapes head has been used successfully to treat mixed hearing loss. Coupling between the floating mass transducer of the VSB and the stapes head is technically less demanding than incus vibroplasty and is more likely to generate a positive outcome without significantly changing residual hearing or resulting in medical or su...

We report our study on nonlinear parity-time (PT) symmetric coupler from a dynamical perspective. In the linear regime, the differential equations governing the dynamics of the coupler, under some parametric changes, can be solved exactly. But with the inclusion of nonlinearity, analytical solution of the system is a rather complicated job. And the sensitiveness of the system on the initial con...

The scope of this paper is to analyze the performance of augmented gain EDFA systems using Single and Multi-wavelength Input sources. The Performance of an Optical Communication system can be improved by the use of EDFAs as an Optical Amplifier. Erbium doped fiber amplifier (EDFA) is an important element in DWDM networks. We can achieve a flat gain spectrum by modeling the dynamic characteristi...

An active isolator achieving both high isolation and low insertion loss at 2.45 GHz is proposed. The based on an asymmetric coupler designed to leverage the gain reverse of amplifier coupling coefficients between input output coupler. are enhanced by using coefficients, power level with optimal can be determined for a target specification. increases handling capability proposed that has coeffic...

The purpose of this project was to establish a maximum acceptable equivalent input noise level (EINL) for hearing aids. It was found that, if the version of the National Acoustic Laboratories (NAL) procedure for selecting the gain and frequency response of hearing aids, which includes modifications for severe and profound hearing loss is used, the EINL criterion can be relaxed for higher gain h...

In this letter, a high-gain low-profile dual-circularly polarized (CP) leaky-wave antenna (LWA) with fixed beam is presented. The proposed LWA comprises only two-layered substrates, in which the top layer constructs annular array while bottom realizes feeding network. To obtain beam, differential excitation generated by coupler employed. Furthermore, dual-CP network provides two sequentially ro...

Packet-switching characteristics are optimized across an integrated 4 x 4 optical cross-point switch matrix based on active vertical coupler switch cells. Optical gain is demonstrated across the entire matrix with a <3-dB difference between the shortest and longest switching paths.

We study the propagation of linear waves and solitons in an array of optical waveguides with an embedded defect created by a pair of waveguides with gain and loss satisfying the socalled parity-time (PT ) symmetry condition. We demonstrate that in the case of small soliton amplitudes, the linear theory describes the scattering of solitons with a good accuracy. We find that the incident high-amp...