info:eu-repo/semantics/article
Quantum dynamics under coherent and incoherent effects of a spin bath in the Keldysh formalism: Application to a spin swapping operation
Fecha
2005-12Registro en:
Danieli, Ernesto Pablo; Pastawski, Horacio Miguel; Alvarez, Gonzalo Agustin; Quantum dynamics under coherent and incoherent effects of a spin bath in the Keldysh formalism: Application to a spin swapping operation; Elsevier Science; Chemical Physics Letters; 402; 1-3; 12-2005; 88-95
0009-2614
CONICET Digital
CONICET
Autor
Danieli, Ernesto Pablo
Pastawski, Horacio Miguel
Alvarez, Gonzalo Agustin
Resumen
We develop the Keldysh formalism for the polarization dynamics of an open spin system. We apply it to the swapping between two qubit states in a model describing an NMR cross-polarization experiment. The environment is a set of interacting spins. For fast fluctuations in the environment, the analytical solution shows effects missed by the secular approximation of the quantum master equation for the density matrix: a frequency decrease depending on the system-environment escape rate and the quantum quadratic short time behavior. Considering full memory of the bath correlations yields a progressive change of the swapping frequency.