Decoherence under many-body system-environment interactions: a stroboscopic representation based on a fictitiously homogenized interaction rate

GONZALO A. ÁLVAREZ; ERNESTO P. DANIELI; PATRICA R. LEVSTEIN; HORACIO M. PASTAWSKI

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Lugar: New York; Año: 2007 vol. 75 p. 621161 - 6211611

1050-2947

An environment interacting with portions of a system leads to multiexponential interaction rates. Within theKeldysh formalism, we fictitiously homogenize the system-environment interaction yielding a uniform decayrate facilitating the evaluation of the propagators. Through an injection procedure we neutralize the fictitiousinteractions. This technique justifies a stroboscopic representation of the system-environment interaction whichis useful for numerical implementation and converges to the natural continuous process. We apply this procedureto a fermionic two-level system and use the Jordan-Wigner transformation to solve a two-spin swappinggate in the presence of a spin environment.