04/28/2026
Department of Physics and Astronomy Colloquium
Place and Date: Tuesday April 28th, 4:00 pm in Lewis 101
Speaker : Prof. Steve Winter, Wake Forest University
Title: Effective Hamiltonian Approaches for Quantum Magnets
Abstract:
Quantum materials represent a broad class of systems whose experimental response relies on uniquely quantum aspects such as entanglement, Berry phases, and electronic correlations. Modeling of such materials presents challenges related to a variety complex behaviors that manifest at different energy scales. In this field, first-principles approaches often provide a vital bridge between experiments and theoretical models. In this talk, I will introduce our numerical strategies for systematically building low-energy models with local charge, spin, and orbital degrees of freedom of arbitrary complexity. I will discuss the insights that these methods have yielded for layered vdW materials, in which spin-orbit coupling induces strongly anisotropic and competing magnetic interactions. Time (and interest) permitting, I will also discuss our work on extending these methods to treat (i) spin-lattice coupling, and (ii) dynamical effective Hamiltonians for modeling non-linear optical responses.
