You are here

Magnetism of layered honeycomb iridates

Seminar
Tuesday, 21.04.2015 15:00

Speakers: Jiří Chaloupka (CEITEC,Přírodovědecká fakulta, Masarykova Universita, Brno)
Place: Na Slovance, main lecture hall
Presented in English
Organisers: Department of Condensed Matter Theory
Abstract: Mutual interactions among magnetic moments in magnetic materials are most frequently of Heisenberg type and thus isotropic in spin space. In Mott insulators containing ions characterized by a large spin-orbit coupling, the on-site entanglement of spin and orbital degrees of freedom translates the bond-directional nature of orbitals into bond-anisotropy of the interactions. Signatures of such bond-anisotropic interactions are found in layered honeycomb iridates such as Na2IrO3. We will study the corresponding spin model containing all the symmetry-allowed nearest-neighbor interaction terms. We will focus in particular on its hidden symmetry properties discovered using dual mappings of the Hamiltonian. Recent experimental results on Na2IrO3 and Li2IrO3 will be reviewed and by a comparison to the theoretical analysis we will localize the realistic parameter range in the global phase diagram of the general spin model.