Abstract
For Lindblad's master equation of open quantum systems with the Hamiltonian in a general quadratic form, the propagator of the density matrix is calculated analytically by using path-integral techniques. The time-dependent density matrix is applied to nuclear barrier penetration in heavy ion collisions with inverted oscillator and double-well potentials. The quantum mechanical decoherence of pairs of phase space histories in the propagator is studied and it is shown that the decoherence depends crucially on the transport coefficients.