In this paper, an input coupler to efficiently couple light from a silicon slab waveguide to a silicon slot waveguide is proposed. The slab waveguide is tapered to slot waveguide dimension for minimum loss. It also allows a miniaturized and compact design. Typical parameter such as taper length is numerically optimized to obtain minimum insertion and return losses as compared to other existing couplers.
Space division multiplexing (SDM) technique is proposed to overcome the bandwidth density drives of short-reach optical transmission systems by utilizing 8-core multicore fiber (MCF). Intercore crosstalk (XT) and higher order modulation format are the most challenging impairments of SDM based optical interconnect (OI) systems. To satisfy the exponential growth of the Internet traffic a frequency interleaving scheme is applied to short-reach MCF OI transmission systems. The negative effects of spectral overlap and intercore XT is reduced by shifting channel frequencies between adjacent cores. To exploit the full potential of SDM power efficient binary phase shift keying (BPSK) modulation format and digital signal processing such as multiple input multiple output (MIMO) equalization are used.
A silicon nanowire waveguide based glucose sensor has been proposed and analyzed. It uses minimal invasive approach to measure the glucose level in a very small blood sample, where, Ethylene-diamine-tetraacetic acid (EDTA) as an anticoagulant, sodium fluoride as preservative and blood sample measurand are added in the ratio of 8:1:1. As the glucose concentration in the blood sample varies, the refractive index (RI) of blood changes, accordingly the refractive index of the solution with 10% blood also gets altered, which in turn to deviated response of the biosensor. The prediction of glucose level is affirmed by taking this solution as a cladding measurand of waveguide. Silicon Nanowire Optical Rectangular Waveguide (SNORW) is proposed for the first time in bio-sensing application for the detection of blood glucose. It works on the principle of detecting changes in refractive index for various concentrations of glucose level ranging from 10 mg/dl to 200 mg/dl. Additionally, SNORW sensor characteristics are compared accordingly with the slot waveguide sensors.
This paper focus on the theoretical investigation of quantum confined Stark effect (QCSE) in strain compensated SiGeSn/GeSn single quantum well (QW). Eigen energies in presence of electric field, for Г valley conduction band (Г- CB) and heavy hole band (HH)) are obtained from the self consistent solution of coupled Schrödinger and Poisson equations by finite difference method. Absorption coefficient considering excitonic effect for direct transition of HH band to Г valley is calculated. A significant shift in absorption peak towards longer wavelengths is observed.