How to mix a density matrix
Quantum Physics
2009-11-07 v2
Abstract
A given density matrix may be represented in many ways as a mixture of pure states. We show how any density matrix may be realized as a uniform ensemble. It has been conjectured that one may realize all probability distributions that are majorized by the vector of eigenvalues of the density matrix. We show that if the states in the ensemble are assumed to be distinct then it is not true, but a marginally weaker statement may still be true.
Keywords
Cite
@article{arxiv.quant-ph/0206169,
title = {How to mix a density matrix},
author = {Ingemar Bengtsson and Asa Ericsson},
journal= {arXiv preprint arXiv:quant-ph/0206169},
year = {2009}
}
Comments
13 pages, 3 figures