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Title: Single biphoton ququarts as either pure or mixed states

Abstract

We analyze features of mixed biphoton polarization states, which arise from pure states of polarization-frequency biphoton ququarts after averaging over frequencies of photons. For mixed states, we find their concurrence C, Schmidt parameter K, degree of polarization P, as well as the von Neumann mutual information I. In some simple cases, we also find the relative entropy S{sub rel} and the degree of classical correlations C{sub cl}. In mixed states, the Schmidt parameter does not characterize the degree of entanglement anymore, as it does in pure states. Nevertheless, the Schmidt parameter remains useful even in the case of mixed states because it remains directly related to the degree of polarization. We compare results occurring in the cases of full pure polarization-frequency states of ququarts and mixed states (averaged over frequencies). Differences between these results can be seen in experiments with and without frequency filters in front of a detector.

Authors:
;  [1];  [1];  [2]
  1. A.M. Prokhorov General Physics Institute, Russian Academy of Science, Moscow (Russian Federation)
  2. (Germany)
Publication Date:
OSTI Identifier:
22068679
Resource Type:
Journal Article
Journal Name:
Physical Review. A
Additional Journal Information:
Journal Volume: 84; Journal Issue: 3; Other Information: (c) 2011 American Institute of Physics; Country of input: Syrian Arab Republic; Journal ID: ISSN 1050-2947
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; CORRELATIONS; ENTROPY; FILTERS; MIXED STATE; PHOTONS; POLARIZATION; PURE STATES; QUANTUM ENTANGLEMENT

Citation Formats

Fedorov, M. V., Volkov, P. A., Mikhailova, J. M., and Max-Planck-Institut fuer Quantenoptik, Garching. Single biphoton ququarts as either pure or mixed states. United States: N. p., 2011. Web. doi:10.1103/PHYSREVA.84.032335.
Fedorov, M. V., Volkov, P. A., Mikhailova, J. M., & Max-Planck-Institut fuer Quantenoptik, Garching. Single biphoton ququarts as either pure or mixed states. United States. doi:10.1103/PHYSREVA.84.032335.
Fedorov, M. V., Volkov, P. A., Mikhailova, J. M., and Max-Planck-Institut fuer Quantenoptik, Garching. Thu . "Single biphoton ququarts as either pure or mixed states". United States. doi:10.1103/PHYSREVA.84.032335.
@article{osti_22068679,
title = {Single biphoton ququarts as either pure or mixed states},
author = {Fedorov, M. V. and Volkov, P. A. and Mikhailova, J. M. and Max-Planck-Institut fuer Quantenoptik, Garching},
abstractNote = {We analyze features of mixed biphoton polarization states, which arise from pure states of polarization-frequency biphoton ququarts after averaging over frequencies of photons. For mixed states, we find their concurrence C, Schmidt parameter K, degree of polarization P, as well as the von Neumann mutual information I. In some simple cases, we also find the relative entropy S{sub rel} and the degree of classical correlations C{sub cl}. In mixed states, the Schmidt parameter does not characterize the degree of entanglement anymore, as it does in pure states. Nevertheless, the Schmidt parameter remains useful even in the case of mixed states because it remains directly related to the degree of polarization. We compare results occurring in the cases of full pure polarization-frequency states of ququarts and mixed states (averaged over frequencies). Differences between these results can be seen in experiments with and without frequency filters in front of a detector.},
doi = {10.1103/PHYSREVA.84.032335},
journal = {Physical Review. A},
issn = {1050-2947},
number = 3,
volume = 84,
place = {United States},
year = {2011},
month = {9}
}