We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Geometric phase as a determinant of a qubit- environment coupling.
- Authors
Dajka, J.; Łuczka, J.; Hänggi, P.
- Abstract
We investigate the qubit geometric phase and its properties in dependence on the mechanism for decoherence of a qubit weakly coupled to its environment. We consider two sources of decoherence: dephasing coupling (without exchange of energy with environment) and dissipative coupling (with exchange of energy). Reduced dynamics of the qubit is studied in terms of the rigorous Davies Markovian quantum master equation, both at zero and non-zero temperature. For pure dephasing coupling, the geometric phase varies monotonically with respect to the polar angle (in the Bloch sphere representation) parameterizing an initial state of the qubit. Moreover, it is antisymmetric about some points on the geometric phase-polar angle plane. This is in distinct contrast to the case of dissipative coupling for which the variation of the geometric phase with respect to the polar angle typically is non-monotonic, displaying local extrema and is not antisymmetric. Sensitivity of the geometric phase to details of the decoherence source can make it a tool for testing the nature of the qubit-environment interaction.
- Subjects
DETERMINANTS (Mathematics); INFORMATION processing; QUANTUM theory; MARKOV processes; REPRESENTATIONS of groups (Algebra); EXTREMAL problems (Mathematics)
- Publication
Quantum Information Processing, 2011, Vol 10, Issue 1, p85
- ISSN
1570-0755
- Publication type
Article
- DOI
10.1007/s11128-010-0178-x