arXiv:cond-mat/0307024 · Physical Review B

Double quantum dot turnstile as an electron spin entangler

Xuedong Hu, S. Das Sarma

Published Mar 12, 2004• 31 citations

Abstract

We study the conditions for a double quantum dot system to work as a reliable electron spin entangler and the efficiency of a beam splitter as a detector for the resulting entangled electron pairs. In particular, we focus on the relative strengths of the tunneling matrix elements, the applied bias and gate voltage, the necessity of time-dependent input/output barriers, and the consequence of considering wave packet states for the electrons as they leave the double dot to enter the beam splitter. We show that a double quantum dot turnstile is, in principle, an efficient electron spin entangler or entanglement filter because of the exchange coupling between the dots and the tunable input/output potential barriers, provided certain conditions are satisfied in the experimental setup.

DOI: 10.1103/physrevb.69.115312

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