Speaker: Cristian Batista, Los Alamos National Laboratory
Abstract: Mott insulators are one of the most important classes of materials in modern solid-state physics. I will show that geometrically frustrated Mott insulators can exhibit unexpected charge effects like spontaneous circular electric currents that result from certain (scalar) chiral spin orderings or non-uniform electronic charge distributions associated with a subclass of bond orderings. We will see how these phases can appear in simple Hubbard models. In addition, I will show how these low-energy spin states contribute comparably to the dielectric and magnetic response functions, leading to interesting phenomena such as dipole-active ESR transitions, rotation the electric field polarization, and magneto-electric effects.