Séminaire commun avec le LPTHE. Horaire et salle exceptionnels: bibilothèque du LPTHE (tours 13-14, 4ème étage) vendredi à 11h
Dynamics in quantum antiferromagnets
Maxime Dupont (U.C. Berkeley)
Theoretically challenging, the understanding of the dynamical response in quantum magnets is of great interest, in particular for both inelastic neutron scattering (INS) and nuclear magnetic resonance (NMR) experiments. In this talk, I will address this question for quasi-one-dimensional quantum magnets, e.g., weakly coupled spin chains for which many compounds are available in nature. In this class of systems, the dimensional crossover between a three-dimensional ordered regime at low temperature towards one-dimensional physics at higher temperature is a nontrivial issue, notably difficult concerning dynamical properties. I will present a comprehensive theoretical study based on both analytical calculations and numerical simulations which allows us to describe the full temperature crossover for the NMR relaxation rate 1/T1, from one-dimensional Tomonaga-Luttinger liquid physics to the three-dimensional ordered regime, as a function of interchain couplings.