Fyzikální ústav Akademie věd ČR

Off-diagonal order in materials close to spin-state transition

Seminář Úterý, 08.10.2013 15:00 - 16:00

Přednášející: Jan Kuneš (Oddělení magnetik a supravodičů, FZÚ AV ČR, v.v.i.)
Místo: Na Slovance, přednáškový sál v přízemí
Jazyk: anglicky
Pořadatelé: Oddělení teorie kondenzovaných látek

Abstract: Using linear response formalism we have performed an unbiased search for particle-hole instabilities in the two-band Hubbard model close to the high-spin--low-spin transition. In addition to the previously reported Ising transition to an ordered arrangement of HS and LS sites we have found an instability towards condensation of spinful excitons. We will present numerical results obtained with dynamical mean-field theory as well as analytic expressions in the strong and weak coupling limits. We will discuss the symmetry aspects of the excitonic phase, connection to the physics of hard-core bosons, experimentally studied in the context of cold atoms, and possible implications for electronic materials.

Copyright © 2008-2010, Fyzikální ústav AV ČR, v. v. i.