Quantum Correlations in Two-Fermion Systems
Abstract
We characterize and classify quantum correlations in two-fermion systems having 2K single-particle states. For pure states we introduce the Slater decomposition and rank (in analogy to Schmidt decomposition and rank), i.e. we decompose the state into a combination of elementary Slater determinants formed by mutually orthogonal single-particle states. Mixed states can be characterized by their Slater number which is the minimal Slater rank required to generate them. For K=2 we give a necessary and sufficient condition for a state to have a Slater number of 1. We introduce a correlation measure for mixed states which can be evaluated analytically for K=2. For higher K, we provide a method of constructing and optimizing Slater number witnesses, i.e. operators that detect Slater number for some states.
Cite
@article{arxiv.quant-ph/0012094,
title = {Quantum Correlations in Two-Fermion Systems},
author = {John Schliemann and J. Ignacio Cirac and Marek Kus and Maciej Lewenstein and Daniel Loss},
journal= {arXiv preprint arXiv:quant-ph/0012094},
year = {2009}
}
Comments
9 pages, some typos corrected and introduction modified, version to be published in Phys. Rev. A