Quantifying nonorthogonality
Abstract
An exploratory approach to the possibility of analyzing nonorthogonality as a quantifiable property is presented. Three different measures for the nonorthogonality of pure states are introduced, and one of these measures is extended to single-particle density matrices using methods that are similar to recently introduced techniques for quantifying entanglement. Several interesting special cases are considered. It is pointed out that a measure of nonorthogonality can meaningfully be associated with a single mixed quantum state. It is then shown how nonorthogonality can be unlocked with classical information; this analysis reveals interesting inequalities and points to a number of connections between nonorthogonality and entanglement.
Cite
@article{arxiv.quant-ph/9907110,
title = {Quantifying nonorthogonality},
author = {Oliver Cohen},
journal= {arXiv preprint arXiv:quant-ph/9907110},
year = {2009}
}
Comments
Accepted for publication in Phys. Rev. A