Rolando Valdés Aguilar
National Institute of Standards and Technology, Gaithersburg, MD.
In this tutorial I will introduce the concept of magnon as the fundamental excitation of a magnetically ordered state. I will discuss magnons both in terms of their semiclassical and quantum descriptions. Then, I will expose on two widely used techniques that can probe magnons at the Brillouin zone center: terahertz and Raman spectroscopy. I will present examples that range from “regular” ordered magnets with large atomic spin, to quantum magnets with psuedo-spin ½ degrees of freedom, and show how to use the magnetic and temperature dependence of their energies to extract Hamiltonian model parameters. Finally, if time permits, I will show how to potentially identify topological magnons using Raman scattering.