Quantum Matter Seminar

Understanding the emergence and dynamics of collective excitations in many-body interacting systems has been a crosscutting theme throughout many branches of physics. In this talk, I will present two experiments on the nonlinear electrodynamic response of materials that show how these excitations arise and lead to non-equilibrium instabilities, revealing deep parallels between condensed matter and high-energy or nuclear physics.

First, I will show how we used THz emission spectroscopy to observe a collective excitation, phason, acquiring mass in a charge density wave (CDW) material. Our discovery confirms a theoretical prediction from over 40 years ago and provides direct evidence for Anderson-Higgs type mass generation in a solid-state system.

Next, I will present our recent discovery of a dynamic magneto-chiral instability that amplifies propagating terahertz (THz) waves in a structurally chiral material. This nonequilibrium instability realizes a condensed-matter analog of the chiral magnetic instability predicted in quark-gluon plasmas, highlighting how emergent electrodynamics in chiral materials can mirror fundamental processes in the early universe.