Phases of quantum states in completely positive non-unitary evolution
Quantum Physics
2009-11-07 v2
Abstract
We define an operational notion of phases in interferometry for a quantum system undergoing a completely positive non-unitary evolution. This definition is based on the concepts of quantum measurement theory. The suitable generalization of the Pancharatnan connection allows us to determine the dynamical and geometrical parts of the total phase between two states linked by a completely positive map. These results reduce to the knonw expressions of total, dynamical and geometrical phases for pure and mixed states evolving unitarily.
Keywords
Cite
@article{arxiv.quant-ph/0205146,
title = {Phases of quantum states in completely positive non-unitary evolution},
author = {J. G. Peixoto de Faria and A. F. R. de Toledo Piza and M. C. Nemes},
journal= {arXiv preprint arXiv:quant-ph/0205146},
year = {2009}
}
Comments
2 figures