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Title: Decoherence of a two-qubit system away from perfect symmetry

Abstract

The decoherence of an asymmetric two-qubit system that is coupled via a variable interaction term to a common bath or two individual baths of harmonic oscillators is examined. The dissipative dynamics are evaluated using the Bloch-Redfield formalism. It is shown that the behavior of the decoherence effects is affected mostly by the symmetries between the qubit operator that is coupled to the environment and the temperature, whereas the differences between the two bath configurations are very small. Moreover, it is elaborated that small imperfections of the qubit parameters do not necessarily lead to a drastic enhancement of the decoherence rates.

Authors:
; ; ;  [1]
  1. Physics Department, Arnold Sommerfeld Center for Theoretical Physics, and Center for NanoScience, Ludwig-Maximilians-Universitaet Muenchen, Theresienstrasse 37, 80333 Munich (Germany)
Publication Date:
OSTI Identifier:
20786466
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 72; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.72.052314; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASYMMETRY; ENERGY LEVELS; HARMONIC OSCILLATORS; INTERACTIONS; QUANTUM COMPUTERS; QUBITS; SYMMETRY

Citation Formats

Storcz, M. J., Hellmann, F., Hrelescu, C., and Wilhelm, F. K. Decoherence of a two-qubit system away from perfect symmetry. United States: N. p., 2005. Web. doi:10.1103/PHYSREVA.72.0.
Storcz, M. J., Hellmann, F., Hrelescu, C., & Wilhelm, F. K. Decoherence of a two-qubit system away from perfect symmetry. United States. doi:10.1103/PHYSREVA.72.0.
Storcz, M. J., Hellmann, F., Hrelescu, C., and Wilhelm, F. K. Tue . "Decoherence of a two-qubit system away from perfect symmetry". United States. doi:10.1103/PHYSREVA.72.0.
@article{osti_20786466,
title = {Decoherence of a two-qubit system away from perfect symmetry},
author = {Storcz, M. J. and Hellmann, F. and Hrelescu, C. and Wilhelm, F. K.},
abstractNote = {The decoherence of an asymmetric two-qubit system that is coupled via a variable interaction term to a common bath or two individual baths of harmonic oscillators is examined. The dissipative dynamics are evaluated using the Bloch-Redfield formalism. It is shown that the behavior of the decoherence effects is affected mostly by the symmetries between the qubit operator that is coupled to the environment and the temperature, whereas the differences between the two bath configurations are very small. Moreover, it is elaborated that small imperfections of the qubit parameters do not necessarily lead to a drastic enhancement of the decoherence rates.},
doi = {10.1103/PHYSREVA.72.0},
journal = {Physical Review. A},
number = 5,
volume = 72,
place = {United States},
year = {Tue Nov 15 00:00:00 EST 2005},
month = {Tue Nov 15 00:00:00 EST 2005}
}
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