High-field torque magnetometry as evidence for strong ferromagnetic Kitaev correlations in the Kitaev material Sodium Iridate
Sarbajaya Kundu
Département de physique
Université de Sherbrooke
Présentation en anglais
Lien Zoom: https://umontreal.zoom.us/j/93026432919
Meeting ID: 930 2643 2919
Passcode: écrire en chiffre: un, trois, sept.
Abstract: The Kitaev honeycomb model, proposed by Alexei Kitaev more than a decade ago, has received much attention as a frustrated spin-1/2 model with anisotropic bond-directional interactions, which is exactly solvable and hosts distinct spin liquid ground states. It was soon recognized that the essential ingredients of this model can be reproduced in a class of transition metal compounds which are spin-orbit assisted Mott insulators, the most prominent candidates being Na2IrO3,Li2IrO3 and alpha-RuCl3. In this talk, I will give a brief introduction to these so-called 'Kitaev materials', and in this context, talk about our recent work on the Kitaev candidate, Na2IrO3, where we combine high-field torque magnetometry measurements, up to a field of 60 T, with numerical exact diagonalization computations on different classes of extended Kitaev-Heisenberg models. From our analysis, we find that a characteristic robust peak-dip feature observed in the experimental torque response can only be reproduced by models with a large ferromagnetic Kitaev interaction and not by their antiferromagnetic Kitaev counterparts. Moreover, we also find evidence for short-range spin correlations in the intermediate field regime, possibly indicating a field-induced transition to a spin liquid phase in this material, signaled by the peak-dip feature.
Cette conférence est présentée par le RQMP.
