Electrical measurement of a two-electron spin state in a double quantum dot

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.

4pages, 2figures

References in corpus (3)

• Coherent control of a single electron spin with electric fields
• Singlet-triplet decoherence due to nuclear spins in a double quantum dot
• Spin-orbit mediated anisotropic spin interaction in interacting electron systems