Numerical investigation of supercontinuum generation and optical frequency combs in Si N-based PCF with high nonlinear coefficient

In this paper, a photonic crystal fiber(PCF) with a dispersion-engineered and high nonlinear coefficient has been designed for supercontinuum generation(SCG) and frequency comb generation(FCG). The proposed PCF has a Si_(3)N_(4) rod in the core. This rod provides more optical confinement in the core by increasing the refractive index of the core. This high confinement reduces the effective mode area of PCF and thus increases the nonlinear coefficient.

Four-Channel Label-Free Photonic Crystal Biosensor Using Nanocavity Resonators

In this paper, we design and characterize a novel small size four-channel biosensor based on the two-dimensional photonic crystal with introducing waveguides and nano-cavities in the hexagonal lattice of air pores in the silicon slab. By removing a group of air pores, waveguides are achieved, and nano-cavities are shaped by modifying the radius of air pores. Highly parallel operation of this biosensor due to the special architecture is the capability of the designed structure. The biomaterials which are suspended in a liquid medium inside nano-cavities cause effective refractive index changes which lead to the resonant wavelength shift in the output terminal. According to results, with increasing the refractive index of nano-cavities, resonant wavelengths shifts to longer values. For biochemical sensing like DNA molecule and protein and for the refractive index detection, this novel designed biosensor can be utilized.

An Optical MIM Pressure Sensor Based on a Double Square Ring Resonator

In this paper, we have proposed a metal-insulator-metal （MIM） pressure sensor which consists of two plasmonic waveguides and a double square ring resonator. The two square rings are connected via a rectangular patch located between the two of them. The surface plasmon polaritons （SPPs） can be transferred from a square ring to the other through this patch. The finite-difference time-domain method （FDTD） has been used to simulate the device. Applying a pressure on the structure, it deforms, and a red shift of 103 nm in the resonance wavelength has been calculated. The deformation is linearly proportional to the wavelength shift in a wide range of wavelength. The proposed optical plasmonic pressure sensor has a sensitivity of 16.5nm/MPa which makes it very suitable for using in biological and biomedical engineering.

Transfer matrix modeling of avalanche photodiode

In this article, we calculated and modeled the gain of Ino.53Gao.47As/[nP avalanche photodiode （APD） based on a device mechanism and carrier rate equations using transfer matrix method （TMM）. In fact, a distributed model was presented for calculating impact ionization （I2） and relating different sections of the multiplication region. In this proposed model, recessive equations were used, and device gain is considered proportional to the number of output photo-electrons and photo-holes. By comparison of simulated results with experimental data available in literature, it has been demonstrated the capability of the developed model as a powerful tool for simulating APDs＇ behavior and interpreting their experimentally measured characteristics.