The loss of quantum coherence induced by a Gaussian random potential

We investigate the source of decoherence from a random external potential by the Feynman path integral method. We find that the off-diagonal elements of the density matrix decay with two characteristic time scales, which are separated by the correlation length. The heavy and light mass cases are demonstrated. ► Effects of Gaussian random potential on quantum coherence using path integral method. ► Off-diagonal elements of the density matrix decay with two characteristic time scales. ► Decoherence of heavy and light masses controlled by a range of coherence lengths.