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arXiv · 0904.3226

Thermopower-enhanced efficiency of Si/SiGe ballistic rectifiers

D. Salloch·U. Wieser·U. Kunze·T. Hackbarth
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Abstract

Injection-type ballistic rectifiers on Si/SiGe are studied with respect to the influence of gate voltage on the transfer resistance RT (output voltage divided by input current) for different positions of a local gate electrode. The rectifiers are trifurcated quantum wires with straight voltage stem and oblique current-injecting leads. Depending on the gate configuration, thermopower contributions arise from nearly-pinched stem regions which either cancel each other or impose upon the ballistic signal with same or opposite polarity. At best, this enhances RT to a maximum value of 470 Ohm close to threshold voltage.

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D. Salloch, U. Wieser, U. Kunze, T. Hackbarth. 2009-04-21. Thermopower-enhanced efficiency of Si/SiGe ballistic rectifiers. https://doi.org/10.1063/1.3140439

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