In this paper, considering optical feedback as an optical injection, and taking in to account round-trip time role in the external cavity, a standard small signal analysis is applied on laser rate equations. By considering the relaxation oscillation (f2) and external cavity frequencies (f) ratio for semiconductor laser, field amplitude response gain, optical phase and carrier number for long ex...

An experimental study over the optical response of thin MoS2 films grownby chemical bath deposition (CBD) method is presented. As two important factors, theeffect of bath temperature and growth time are considered on the photocurrentgeneration in the grown samples. The results show that increasing the growth time leadsto better optical response and higher difference betw...

This work presents ZnO nanorods coated multimode optical fiber sensing behavior in response to ethanol solution. The sensor operates based on modulation of light intensity which arises from manipulation of light interaction with the ambient environment in sensing region. For this purpose, two steps are experimentally applied here; etching and then coating fiber with ZnO nanorods to provide stro...

for an indoor non-directed line of sight optical wireless communication (nlos-owc) system we investigate the optimized lambertian order (olo) of light-emitting diodes (leds). we firstly derive an expression for the olo from a conventional lambertian led model. then, we analyze the indoor multi-cell nlos-owc channel characteristics including the optical power distribution and the multipath time ...

in this paper, based on the coupled-mode and carrier rate equations, a dynamic model and numerical analysis of a multi quantum well (mqw) chirped distributed feedback semiconductor optical amplifier (dfb-soa)  all-optical flip-flop is precisely derived. we have analyzed the effects of strains of qw and mqw and cross phase modulation (xpm) on the dynamic response, and rise and fall times of the ...

application of polymers in novel and advanced scientific technologies is increasingly expanding. in this regard, optical polymers among different materials have found a special and unique position. a novel dye doped polymer thin film was prepared by taking advantage of dye molecules' interaction with the host environment. this sample, like self-assembled structures, makes use of this inter...

Static properties, relatively intensity noise and intensity modulation response in quantum cascade lasers (QCLs) studied theoretically in this paper. The present rate equations model consists of three equations for the electrons density in the conduction band and one equation for photons density in cavity length. Two equations were derived to calculate the noise and modulation response. Calcula...

In this paper, based on the coupled-mode and carrier rate equations, a dynamic model and numerical analysis of a multi quantum well (MQW) chirped distributed feedback semiconductor optical amplifier (DFB-SOA)  all-optical flip-flop is precisely derived. We have analyzed the effects of strains of QW and MQW and cross phase modulation (XPM) on the dynamic response, and rise and fall times of the ...

This paper introduces an optical measurement system for shock wave characteristics. The system works by mountinga metal plate attached to spring mounts against the shock wavefront. This set is sealed and can plot the shock wave pressure diagram by measuring plate's displacement, radiation and changing the reflection of light during shock wave conflict, and converting these optical data to volta...

transfer matrix method (tmm) has been applied to analyze characteristics of semiconductor laser optical amplifiers. the input signal is sinusoidal modulating wave and we do not assume the modulating bias signal as well. we have shown that the distoration arises from gain modulation at low modulation frequencies, but in microwave modulation frequencies, the gain takes an average value and the re...