arXiv:0907.4191 · Physical Review Letters

Electrical Measurement of a Two-Electron Spin State in a Double Quantum Dot

Nobuhiko Yokoshi, Hiroshi Imamura, Hideo Kosaka

Published Jul 23, 2009• 9 citations

Abstract

We propose a scheme for electrical measurement of two-electron spin states in a semiconductor double quantum dot. We calculated the adiabatic charge transfer when surface gates are modulated in time. Because of spin-orbit coupling in the semiconductor, spatial displacement of the electrons causes a total spin rotation. It follows that the expectation value of the transferred charge reflects the relative phase as well as the total spin population of a prepared singlet-triplet superposition state. The precise detection of the charge transfer serves to identify the quantum superposition.

DOI: 10.1103/physrevlett.103.046806

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