Classical and quantum correlations in an ideal gas of particles obeying fractional exclusion statistics
Department of Physics, University of Pune,
Received: 10 May 2012
Received in final form: 17 August 2012
Published online: 27 November 2012
We study the correlations in a two component gas of non-interacting particles obeying fractional exclusion statistics characterized by a parameter α ∈ [0, 1] that interpolates between bosonic (α = 0) and fermionic (α = 1) statistics. We discuss the behaviour of the total correlations, entanglement, classical correlations and quantum discord in the two spin density matrix (‘spin’ here refers to the two internal degrees of freedom) as a function of the statistical parameter α and the relative distance between the two spins. We show that the spins are entangled only for statistics α > α∗ = 2/3 (independent of the number of spatial dimensions) and provided that the relative distance between the spins is less than a certain critical value re which depends on the Fermi wave number and the statistics parameter. However, the quantum discord is non-vanishing even in the absence of entanglement, vanishing (for zero temperature) only in the limit of very large relative separations, i.e., at distances where quantum statistics play no role.
Key words: Quantum Information
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2012