Issue
EPL
Volume 88, Number 1, October 2009
Article Number 10006
Number of page(s) 4
Section General
DOI http://dx.doi.org/10.1209/0295-5075/88/10006
Published online 26 October 2009
EPL, 88 (2009) 10006
DOI: 10.1209/0295-5075/88/10006

Correlation in quantum states of two identical particles

D. L. Zhou

Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences - Beijing 100080, China

zhoudl72@aphy.iphy.ac.cn

received 8 August 2009; accepted in final form 23 September 2009; published October 2009
published online 26 October 2009

Abstract
We identify the correlation in a state of two identical particles as the residual information beyond what is already contained in the 1-particle reduced density matrix, and propose a correlation measure based on the maximum entropy principle. We obtain the analytical results of the correlation measure, which make it computable for arbitrary two-particle states. We also show that the degrees of correlation in the same two-particle states with different particle types will decrease in the following order: bosons, fermions, and distinguishable particles.

PACS
03.65.Ud - Entanglement and quantum nonlocality (e.g. EPR paradox, Bell's inequalities, GHZ states, etc.).
03.67.Mn - Entanglement measures, witnesses, and other characterizations.
89.70.Cf - Entropy and other measures of information.

© EPLA 2009