Study of Dissipative System of Charged Particles by Wigner's Functions
  Recently, it is shown that the extended phase space formulation of quantum mechanics is a suitable technique for studying the quantum dissipative system. Here, as an application of this formalism, we consider a dissipative system of charged particles interacting with an external time dependent electric field. Such a system has been investigating by Buch and Denman, and two solutions with completely different structure have been obtained for Schr\"{o}dinger's equation in two different gauges. We demonstrate how both gauges lead to the same conductivity by generalizing the gauge transformations to the phase space and using the extended phase space technique. 
S.Khademi, S.Nasiri, S.Fathi, and F.Taati