RT Journal Article
T1 Decoherence due to an excited state quantum phase transition in a two-level boson model
A1 Pérez Fernández, Pedro
A1 Relaño Pérez, Armando
A1 Arias Carrasco, José Miguel
A1 Dukelsky, J.
A1 García Ramos, José Enrique
K1 Bosones
K1 Quanta, Teoría de los
AB The decoherence induced on a single qubit by its interaction with the environment is studied. The environment is modeled as a scalar two-level boson system that can go through either first-order or continuous-excited-state quantum phase transitions, depending on the values of the control parameters. A mean-field method based on the Tamm-Damkoff approximation is worked out in order to understand the observed behavior of the decoherence. Only the continuous-excited-state phase transition produces a noticeable effect in the decoherence of the qubit. This is maximal when the system-environment coupling brings the environment to the critical point for the continuous phase transition. In this situation, the decoherence factor (or the fidelity) goes to zero with a finite-size scaling power law.
PB American Physical Society
SN 1050-2947
YR 2009
FD 2009-09-17
LK http://hdl.handle.net/10272/5450
UL http://hdl.handle.net/10272/5450
LA eng
NO Pérez Fernández, P., Relaño Pérez, A., Arias Carrasco, J.M., Dukelsky, J., García Ramos, J.E.: "Decoherence due to an excited state quantum phase transition in a two-level boson model". Physical Review A. Vol. 80, n. 3 (2009). ISSN 1050-2947
DS Repositorio Institucional de la Universidad de Huelva
RD 30 may 2026