A first-principles study and some applied researches of high-temperature superconductors and other low-dimensional functional materials

Abstract

This thesis comprises two parts: The first is a fundamental theoretical study of hightemperature superconductors (HTS), addressing the energy balances involved in the superconducting pairing (research started under supervision of Prof. A.J. Leggett, in stays at the University of Illinois at Urbana-Champaign, USA). The study presents an extension, to the case of HTS, of equations originally derived for simple superconductors by G.V. Chester that link the energy saved by the superconductivity with the structural properties of the materials. The second part addresses applied aspects of various micro and nanostructured functional materials, including both HTS (optimization of superconducting devices, as bolometric radiation sensors, hybrid piezoelectric-superconducting films, and other) and electrostatic nanostructured microporous (ENM) media for nanofluid filtration.