Quantum Magnetism in Iridium Oxides: From Heisenberg to the Compass and Kitaev models
Seminars
Theory of Condensed Matter – Seminar “Statistical Mechanics”
Date and Time: Tuesday, 17 April 2018, at 4:00 PM
Venue: Conference Hall (2nd floor), the Bogoliubov Laboratory of Theoretical Physics
Seminar topic: «Quantum Magnetism in Iridium Oxides: From Heisenberg to the Compass and Kitaev models»
Speaker: V. Yushankhai (Bogoliubov Laboratory of Theoretical Physics, JINR)
Abstract:
In 5d iridium oxides a large spin-orbit coupling, inherent to heavy 5d elements, gives rise to a variety of electronic phases including a novel Jeff=1/2 Mott insulator. Magnetic lattice models for this insulator are formulated in terms of Kramers doublets and show the peculiar bond-directional (compass) anisotropic exchange between Jeff=1/2 pseudospins. In planar iridium oxides Na2IrO3 and Li2IrO3, exchange coupling between pseudospins placed on a honeycomb lattice is described by the famous Kitaev honeycomb model, as was theoretically derived by Jackeli and Khaliullin in 2009. In the present talk, a short introduction into the Kitaev’s model will be given in connection with recent developments in the field of quantum magnetism of iridium oxides.