Thermodynamic anomaly of the free damped quantum particle: the bath perspective

A possible definition of the specific heat of open quantum systems is based on the reduced partition function of the system. For a free damped quantum particle, it has been found that under certain conditions, this specific heat can become negative at low temperatures. In contrast to the conventional approaches focusing on the system degree of freedom, here we concentrate on the changes induced in the environment when the system is coupled to it. Our analysis is carried out for an Ohmic environment consisting of harmonic oscillators and allows to identify the mechanism by which the specific heat becomes negative. Furthermore, the formal condition for the occurrence of a negative specific heat is given a physical interpretation in terms of the total mass of bath oscillators and the system mass.Comment: 7 pages, 1 figure, final version after one round of refereein

Self-consistent Hartree-Fock approximation for non-equilibrium electron transport through nanostructures

We present the formulation of self-consistent Hartree-Fock theory for non-equilibrium electron transport in nanostructures. The derivations are performed by our method for direct calculations of asymptotic, non-equilibrium steady state averages. We use asymptotic single-particle density matrix to approximate the molecular Hamiltonian by its Hartree-Fock form. Then we obtain the close system of coupled nonlinear integral equations for the transformation matrix, which diagonalizes the Hartree-Fock Hamiltonian, and asymptotic single particle density matrix

To the derivation of kinetic equations in the case of non-Poissonian statistics and a finite duration of collisions

Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome / CNR - Consiglio Nazionale delle RichercheSIGLEITItal