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In contrast to graphene, which is a gapless semiconductor, graphane, the hydrogenated graphene, is a semiconductor with an energy gap. Together with the 2-D geometry, unique transport features of graphene, and the possibility of doping graphane, p and n regions can be defined so that 2-D p-n junctions become feasible with small reverse currents. This paper introduces a basic analysis to obtain the current-voltage characteristics of such a 2-D p-n junction based on graphane. As we show, within the approximation of Shockley's law of junctions, an ideal I-V characteristic for this p-n junction is to be expected  

Graphane is a semiconductor with an energy gap, obtained from hydrogenation of the two-dimensional grapheme sheet. Together with the two-dimensional geometry, unique transport features of graphene, and possibility of doping graphane, p and n regions can be defined so that p-n junctions become feasible with small reverse currents. Our recent analysis has shown that an ideal I-V characteristic for this type of junctions may be expected. Here, we predict the behavior of bipolar juncrion transistors based on graphane. Profiles of carriers and intrinsic parameters of the graphane transistor are calculated and discussed  

We study the effects of recombination and generation process on the operation of bipolar junction transistor based on two-dimensional materials, and in particular, graphone. Here, we use Shockley-Read-Hall model to study these process. First, we investigate the current-voltage characteristics of a graphone p-n junction considering generation and recombination process. Then, we calculate the estimated changes in current gain, cutoff frequency, and output characteristics of a graphone bipolar junction transistor designed in a recent study  

The theory of silicon optical modulators of ring resonators based on PN diode in reverse bias is primarily discussed. It secondarily provides a full-featured simulator to investigate the behavior of such modulators. Wave equation for ring structure will be solved by using the conformal transformation method and the matrix method as it was used to analyze bent planar optical waveguides. Power coupling between ring and straight waveguides will be calculated by coupled theory of nonparallel waveguides based on experimental results. The time response demonstrates the capability of this device to operate correctly at up to 10 Gbs-1 bitrate, and the frequency spectrum analysis of device shows a >... 

Abstract We design a thermo-photovoltaic Tandem cell which produces high open circuit voltage (Voc) that causes to increase efficiency (η). The currently used materials (AlAsSb-InGaSb/InAsSb) have thermo-photovoltaic (TPV) property which can be a p-n junction of a solar cell, but they have low bandgap energy which is the reason for lower open circuit voltage. In this paper, in the bottom cell of the Tandem, there is 30 quantum wells which increase absorption coefficients and quantum efficiency (QE) that causes to increase current. By increasing the current of the bottom cell, the top cell thickness must be increased because the top cell and the bottom cell should have the same current. In...