DECOHERENCE AND INITIAL CORRELATIONS IN QUANTUM BROWNIAN MOTION

LUCIANA DAVILA ROMERO; JUAN PABLO PAZ

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Lugar: New York; Año: 1997 vol. 55 p. 4070 - 4085

1050-2947

We analyze the evolution of a quantum Brownian particle starting from an initial state that contains correlations between this system and its environment. Using a path-integral approach, we obtain a master equation for the reduced density matrix of the system finding relatively simple expressions for its time-dependent coefficients. We examine the evolution of delocalized initial states ~Schro¨dinger cats! investigating the effectiveness of the decoherence process. Analytic results are obtained for an Ohmic environment ~Drude?s model! at zero temperature.