Nonequilibrium Reduced-Density Operator for Nanoscopic Systems
1 Quantum Physics Division, Faculty of Physics A. Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland
Acta Physica Polonica A, 102, 717-727 (2002)
Retarded forms of the nonequilibrium reduced-density operator are derived from the generalized Schrödinger variational principle of a system with both mechanical and thermal perturbations, taking into account the additional condition that the values of generalized thermodynamic coordinates are fixed at infinitely remote past. This reduced density operator may be useful in describing nonequilibrium properties of nanoscopic and mesoscopic systems, as well as ultrathin films. With the help of this reduced-density operator the generalized Green--Kubo formulae are obtained.