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arXiv · 0709.0182

Bell-state preparation for electron spins in a semiconductor double quantum dot

Robert Roloff·Walter Pötz
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Abstract

A robust scheme for state preparation and state trapping for the spins of two electrons in a semiconductor double quantum dot is presented. The system is modeled by two spins coupled to two independent bosonic reservoirs. Decoherence effects due to this environment are minimized by application of optimized control fields which make the target state to the ground state of the isolated driven spin system. We show that stable spin entanglement with respect to pure dephasing is possible. Specifically, we demonstrate state trapping in a maximally entangled state (Bell state) in the presence of decoherence.

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Robert Roloff, Walter Pötz. 2007-09-03. Bell-state preparation for electron spins in a semiconductor double quantum dot. https://doi.org/10.1103/physrevb.76.075333

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