Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Nanoscale single-electron transistor architectures for single spin detection in solid state quantum computer devices

Tilo M. Buehler, R. Brenner, D. J. Reilly, A. R. Hamilton, Andrew S. Dzurak, Robert G. Clark

Published Nov 19, 2001• 0 citations

Abstract

Single-spin detection will be crucial for solid-state quantum computer architectures in which information is encoded in the spin-state of single nuclear or electron spins. The formidable problem of single-spin detection in a solid can be mapped to a more tractable problem of single-charge detection through spin-dependent electron transfer which may be observed using ultra-sensitive solid-state nanostructure electrometers. Here we describe a readout architecture using single electron transistors (SETs) that can detect the charge-state of two coupled metal dots, which simulates charge transfer in a two-quantum bit (qubit) spin system. This twin-SET architecture allows significant reduction of random charge noise by correlating two detector outputs, reducing the probability of readout errors in the quantum computer.

DOI: 10.1117/12.454622

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