Effective low-energy descriptions of correlated and inhomogeneous electrons

• Grant number: 23/06094-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2023
• End date: July 31, 2027
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Eric de Castro e Andrade
• Grantee: Lucas Gabriel Rabelo
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 21/06629-4 - Electronic correlations in quantum materials: inhomogeneities and frustration, AP.JP2
• Associated scholarship(s): 25/18719-9 - Effective low-energy descriptions of doped semiconductors, BE.EP.DR

Abstract

Inspired by the singular thermodynamics observed across the metal-insulator transition in doped semiconductors, we investigate the low-temperature behavior of a non-interacting disordered electronic bath coupled to local magnetic moments. In the absence of the moments, the electronic bath displays an Anderson-like metal-insulator transition as a function of doping. We propose to implement a large-N variational approach to study the quenching of these local moments and the evolution of the system thermodynamics across the transition since our variational approach connects the random singlet formation deep into the insulating regime to the disordered Fermi-liquid behavior expected in the metallic phase. The same approach can be used to study heavy-fermion systems, particularly disordered Kondo insulators, where the presence of inhomogeneities often induces a metal-like response and hampers a definitive identification of topological edge states. (AU)