Novel thermodynamic response of frustrated magnets: from magnetization plateaus to thermal Hall effect

• Grant number: 23/13425-1
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: March 01, 2024
• End date: February 29, 2028
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Eric de Castro e Andrade
• Grantee: Gabriel Capelo Domingues
• 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

Abstract

Highly frustrated magnets constitute a prime territory in the quest for novel phases of matter. Those include non-trivial forms of order and disorder, such as quantum spin liquids, spin nematics, vortices, and other topological magnetic textures. In this project, we investigate novel physical responses in frustrated magnets in two different physical systems. We start with the paradigmatic example of the antiferromagnetic Heisenberg model in the Kagome lattice, which displays a quantum spin liquid ground state for spin S=1/2. For non-vanishing second neighbors exchange couplings, long-range ordered phases are stabilized, and in the presence of an external magnetic field, numerical calculations show a m/S=1/3 magnetization plateau. In this project, we would like to investigate the emergence of this plateau and how it is connected to the spin-liquid phase at zero field. As a second system, we consider the thermal Hall response as a tool to probe low-energy excitations in frustrated magnets, mainly because topologically non-trivial magnetic excitation spectrum produces either a quantized or a more pronounced response. Our goal is to access the utility of the thermal Hall coefficient to probe the characteristic response in a family of newly proposed Co-based S=1/2 Kitaev materials.