Classical Kitaev - J1-J2 model in the honeycomb lattice

J. PICCININI; F. A. GÓMEZ ALBARRACÍN; H. D. ROSALES

Buenos Aires

Conferencia; International Conference of Statistical Physics - StatPhys 27; 2019

UBA

In the last years, the Kitaev-Heisenberg model with additional couplings in the honeycomb lattice have attracted a great deal of attention due to their relevance in iridate honeycomb materiales. Furthermore, different exotic phenomena has been explored in the frustated honeycomb lattice for the pure Heisenberg model, such as spin liquid phases, degenerate ground states, thermal and quantum state selection. In this work, we present a study of the effect of the competition between antiferromagnetic exchange couplings up to second nearest neighbours and Kitaev interactions in this lattice for classical spins. We find that in some cases the Kitaev interactions lift the line degeneracy of the Heisenberg model. In others, this degeneracy remains. For strong Kitaev ferromagnetic couplings, our results are compatible with a "stripy" phase, which is expected to be stabilized by quantum fluctuations. We also discuss the possibility of a "zig-zag" phase for ferromagnetic nearest neighbour interactions.