Anagrafe della ricerca

Quantum thermodynamics is a rapidly growing field that meets a critical challenge in quantum technologies: The development of efficient devices that maximize the heat conversion into electricity and minimize heat waste. NEThEQS is a theoretical project that aims to investigate the interplay between quantum coherent phenomena and non-equilibrium thermal effects. By suitably combining the complementary expertise of two Units, PoliTO and NANO-CNR, the project addresses some specific open problems, with a balance between fundamental questions of quantum thermal engines and some of their implementations. At a more fundamental level, we shall first consider a generic bipartite quantum system that converts a temperature gradient into work, acting as a heat engine. We shall investigate whether entanglement and other kinds of quantum correlations can improve the efficiency of a thermodynamic cycle. Then, we will extend the study to the multipartite case, by comparing the performance of machines in uncorrelated states and different kinds of multipartite quantum correlations. At a more applicative level, we shall study specific implementations of thermal engines. Focussing first on spin-orbit coupled nanowires, whose promising thermoelectric applications have been overshadowed by the search for Majorana states, we shall investigate whether their phase-coherent transport can be exploited to control their thermoelectric response through electron quantum interference. Then, the effects on thermal properties of an additional coherent phenomenon, namely the superconducting pairing, will be analyzed. Furthermore, we shall consider multi-terminal setups involving edge states of topological insulators or Hall systems coupled to superconductors, and we shall analyze the thermoelectric effects generated by a temperature difference between the terminals. Our goal is to clarify the relation between entanglement of Cooper pairs and thermoelectric effects, to compute the correlations of charge, heat and spin currents, and to analyze how these depend on interference effects and electronic interactions. Finally, we aim to explore the time-dependent coherent dynamics and the far from equilibrium regime. We shall investigate how the heat dynamics resulting from the quench of a thermally asymmetric initial state in an isolated quantum system is affected by the presence of topological states or a flux. Also, we shall consider the case of periodically driven systems, and study the efficiency and performances of coherent thermal machines based on topological materials and superconductors. By addressing these challenging problems, NEThEQS is expected to provide a valuable contribution to the technological applications of subKelvin quantum engines and high sensitivity quantum sensors. At the same time, it will contribute to the development of an Italian community in the field of quantum thermodynamics and quantum technologies.