Estimation of the spatial decoherence time in circular quantum dots

We propose a simple phenomenological model to estimate the spatial decoherence time in quantum dots. The dissipative phase space dynamics is described in terms of the density matrix and the corresponding Wigner function, which are derived from a master equation with Lindblad operators linear in the canonical variables. The formalism was initially developed to describe diffusion and dissipation in deep inelastic heavy ion collisions, but also an application to quantum dots is possible. It allows us to study the dependence of the decoherence rate on the dissipation strength, the temperature and an external magnetic field, which is demonstrated in illustrative calculations on a circular GaAs one-electron quantum dot.