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arXiv:quant-ph/0403214 · Physical Review A

Entanglement of electron spins of noninteracting electron gases

Sangchul Oh, Jaewan Kim

Published May 21, 2004• 63 citations
arXivHTMLPDF

Abstract

We study entanglement of electron spins in many-body systems based on the Green's function approach. As an application we obtain the two-particle density matrix of a noninteracting electron gas and identify its two-spin density matrix as a Werner state. We calculate entanglement measures, a classical correlation, mutual information, and a pair-distribution function of two electrons at zero and finite temperatures. We find that changes of entanglement measures are proportional to ${T}^{2}$ at low temperatures.

DOI
10.1103/physreva.69.054305

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