Eur. Phys. J. D (2012) 66: 46
https://doi.org/10.1140/epjd/e2012-20704-6

Regular Article

Quantum discord of electron spins of noninteracting electron gases

¹ School of Electric Engineering and Information, Anhui University of Technology, Ma’ anshan 243002, P.R. China
² Department of Modern Physics, University of Science and Technology of China, Hefei 230026, P.R. China

^a e-mail: mxiaosan79@gmail.com

Received: 4 December 2011
Received in final form: 10 January 2012
Published online: 24 February 2012

Abstract

In this paper, we analyze the quantum discord of electron spins of noninteracting electron gases. Our results imply that the quantum discord depends on the relative distance between the two electrons and the temperature. By a comparison between the quantum discord and the entanglement of formation, we find that the quantum discord is more robust than the entanglement of formation in the sense that the quantum discord takes a zero value only at discrete points of the range of the relative distance whereas the entanglement of formation can disappear for a finite relative distance.