Finite temperature and magnetic field transport in 1D quantum magnets

Date

Nov 12, 2015

Time

2:00 PM - 3:00 PM

Speaker

Xenophon Zotos

Affiliation

University of Crete

Language

en

Main Topic

Physik

Other Topics

Physik

Host

CMT seminars

Description

I’ll present recent exact results on the finite temperature and magnetic field magneto-thermal transport in the one dimensional spin-1/2 Heisenberg model obtained using the Bethe ansatz (BA) method. In particular, I’ll discuss the behavior of spin Drude weight as a function of magnetic field down to low temperatures. Furthermore, I’ll discuss the thermodynamics, thermal transport and dynamics (ESR), of the spin S=1 easy-plane quasi-one dimensional quantum magnet NiCl2-4SC(NH2)2 (DTN). The analysis is based on an effective spin-1/2 anisotropic (s= 1/2) Heisenberg model description. It is put on a firm basis by comparing the thermodynamics of the S=1 model, obtained using TMRG, with exact BA specific heat and magnetization results for the s=1/2 Heisenberg model. For the thermal conductivity in a magnetic field, I’ll compare numerical data on the S=1 model obtained using exact diagonalization techniques to exact results using the BA method. For the ESR data, using a recently developed BA technique, I’ll show that the extremely sharp line observed in experiments, is due to a singular excitation to a single excited state.

Last modified: Nov 12, 2015, 2:12:00 PM