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arXiv · 1005.2793

Manipulation of two spin qubits in a double quantum dot using an electric field

Atsuo Shitade·Motohiko Ezawa·Naoto Nagaosa
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Abstract

We propose purely electric manipulation of spin qubits by means of the spin-orbit interaction (SOI) {\it without magnetic field or magnets} in a double-quantum dot. All the unitary transformations can be constructed by the time-dependent Dzyaloshinsky-Moriya interaction between the two spins, which arises from the Rashba SOI modulated by electric field. As a few demonstrations, we study both analytically and numerically the three operations, i.e., (A) the spin initialization, (B) the two-spin rotation in the opposite directions, and (C) the two-spin rotation in the same direction. The effects of the relaxation and the feasibility of this proposal are also discussed.

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Atsuo Shitade, Motohiko Ezawa, Naoto Nagaosa. 2010-11-05. Manipulation of two spin qubits in a double quantum dot using an electric field. https://doi.org/10.1103/physrevb.82.195305

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