Device modeling and simulation studies of a Cu(In1-x,Gax)Se2 (CIGS) thin film solar cell have been carried out. A variety of graded band-gap structures, including space charge region (SCR) grading, back surface region grading, and double grading of the CIGS absorber layer, are examined. The device physics and performance parameters for different band-gap profiles were analyzed. Based on the sim...

We present a first principle investigation of the electronic structure and the band gap bowing parameter of zinc-blende AlxGa1−xN using both local density approximation and screened-exchange density functional method. The calculated sX-LDA band gaps for GaN and AlN are 95% and 90% of the experimentally observed values, respectively, while LDA underestimates the gaps to 62% and 70%. In contrast ...

This paper presents a single-element microstrip spade-shaped patch antennas with partial ground plane, integrated an electromagnetic band-gap (EBG) structure, and fed feedline to achieve wideband, dual-band band-notched characteristic. Two similar mushroom-like EBG structures built into the wideband antenna were used suppress specific band, resulting in dual-band. The wide-band achieved broad b...