Ganpathy Murthy (University of Kentucky)

Date: Mon. October 12th, 2026, 12:45 pm-1:45 pm
Location: Rockefeller 221 (Foldy room)

Quantum Hall Ferromagnetism in a Cavity

Speaker: Prof. Ganpathy Murthy

Department of Physics and Astronomy, University of Kentucky

(Host: Harsh Mathur)

Abstract: Quantum Hall states are two-dimensional topological insulators, with an insulating bulk and current carrying edges. When the electrons have internal degrees of freedom such as spin and/or valley, quantum Hall states can display spontaneous symmetry breaking, leading to quantum Hall ferromagnets. In the same spirit as cavity quantum electrodynamics, the new field of cavity quantum materials asks how the ground and excited states of quantum materials are affected by being in a cavity. Here, in a specific example, I will show that the simplest quantum Hall ferromagnet at filling factor 1 undergoes a phase transition to an inhomogeneous ground state when coupled sufficiently strongly to an undriven cavity. I will discuss the implications and some open questions.