arXiv subjects

Aldo Di Carlo

Publications and source records attributed to Aldo Di Carlo.

22 records · Page 2Linked to original sources

arXiv2013

Kinetic and thermodynamic temperatures in quantum systems

In this work we present a formalism to describe non equilibrium conditions in systems with a discretized energy spectrum, such as quantum systems. We develop a formalism based on a combination of Gibbs-Shannon entropy and information thermodynamics that arrives to a generalization of the De-Brujin identity applicable to discrete and non-symmetric distributions. This allows to define the concept of a thermodynamic temperature with a different, albeit complementary meaning to the equilibrium kinetic temperature of a system. The theory is applied to Bosonic and Fermionic cases represented by an harmonic oscillator and a single energy state, respectively. We show that the formalism correctly recovers known results at equilibrium, then we demonstrate an application to a genuine non equilibrium state: a coherent quantum oscillator.

cond-mat.stat-mech↗

arXiv2013

Free energy potential and temperature with information exchange

In this paper we develop a generalized formalism for equilibrium thermodynamic systems when an information is shared between the system and the reservoir. The information results in a correction to the entropy of the system. This extension of the formalism requires a consistent generalization of the concept of thermodynamic temperature. We show that this extended equilibrium formalism includes also non-equilibrium conditions in steady state. By non-equilibrium conditions we mean here a non Boltzmann probability distribution within the phase space of the system. It is in fact possible to map non-equilibrium steady state in an equivalent system in equilibrium conditions (Boltzmann distribution) with generalized temperature and the inclusion of the information potential corrections. A simple model consisting in a single free particle is discussed as elementary application of the theory.

cond-mat.stat-mech↗

arXiv2003

Tailorable acceptor ${\rm C}_{60-n}{\rm B}_{n}$ and donor ${\rm C}_{60-m}{\rm N}_{m}$ pairs for molecular electronics

Our first-principles calculations demonstrate that ${\rm C}_{60-n}{\rm B}_{n}$ and ${\rm C}_{60-m}{\rm N}_{m}$ molecules can be engineered as the acceptors and donors, respectively, which are needed for molecular electronics, by properly controlling the number $n$ and $m$ of the substitutional dopants in ${\rm C}_{60}$. As an example, we show that acceptor ${\rm C}_{48}{\rm B}_{12}$ and donor ${\rm C}_{48}{\rm N}_{12}$ are promising components for molecular rectifiers, carbon nanotube-based $p$-type, $n$-type, $n$-$p$-$n$ and $p$-$n$-$p$ transistors and $p$-$n$ junctions.

cond-mat.mtrl-sci↗

arXiv1998

Microscopic theory of quantum-transport phenomena in mesoscopic systems: A Monte Carlo approach

A theoretical investigation of quantum-transport phenomena in mesoscopic systems is presented. In particular, a generalization to ``open systems'' of the well-known semiconductor Bloch equations is proposed. The presence of spatial boundary conditions manifest itself through self-energy corrections and additional source terms in the kinetic equations, whose form is suitable for a solution via a generalized Monte Carlo simulation. The proposed approach is applied to the study of quantum-transport phenomena in double-barrier structures as well as in superlattices, showing a strong interplay between phase coherence and relaxation.

cond-mat.mes-hall↗