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arXiv · cond-mat/0501437

Analysis and Geometric Optimization of Single Electron Transistors for Read-Out in Solid-State Quantum Computing

Abstract

The single electron transistor (SET) offers unparalled opportunities as a nano-scale electrometer, capable of measuring sub-electron charge variations. SETs have been proposed for read-out schema in solid-state quantum computing where quantum information processing outcomes depend on the location of a single electron on nearby quantum dots. In this paper we investigate various geometries of a SET in order to maximize the device's sensitivity to charge transfer between quantum dots. Through the use of finite element modeling we model the materials and geometries of an Al/Al2O3 SET measuring the state of quantum dots in the Si substrate beneath. The investigation is motivated by the quest to build a scalable quantum computer, though the methodology used is primarily that of circuit theory. As such we provide useful techniques for any electronic device operating at the classical/quantum interface.

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BibTeXRIS

Vincent I. Conrad, Andrew D. Greentree, David N. Jamieson, Lloyd C. L. Hollenberg. 2005-01-19. Analysis and Geometric Optimization of Single Electron Transistors for Read-Out in Solid-State Quantum Computing. https://doi.org/10.1166/jctn.2005.105

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