On the Existence and Robustness of Steady Position-Momentum Correlations for Time-Dependent Quadratic Systems

Abstract

We discuss conditions giving rise to stationary position-momentum correlations among quantum states in the Fock and coherent basis associated with the natural invariant for the one-dimensional time-dependent quadratic Hamiltonian operators such as the Kanai-Caldirola Hamiltonian. We also discuss some basic features such as quantum decoherence of the wave functions resulting from the corresponding quantum dynamics of these systems that exhibit no timedependence in their quantum correlations. In particular, steady statistical momentum averages are seen over welldefined time intervals in the evolution of a linear superposition of the basis states of modified exponentially damped mass systems.