Magnetic Properties of the S = 1 Kitaev Model with Anisotropic Interactions

Abstract

We investigate magnetic properties in the S = 1 Kitaev model in the anisotropic limit. Performing the fourth-order perturbation expansion with respect to the x-bonds, y-bonds, and magnetic field, we derive the effective Hamiltonian, where the low-energy physics should be described by the free spins with an effective magnetic field. Making use of the exact diagonalization method for small clusters, we discuss ground-state properties in the system complementary.

Low-temperature properties in the bilayer Kitaev model

“…These results naively expect that the generalized Kitaev model has common magnetic properties. On the other hand, it has been reported that, in the anisotropic Kitaev model with one of the three kinds of bonds being large, the effective Hamiltonian depends on the parity of 2S; its ground state is quantum (classical) for half-integer (integer) spins [25]. Therefore, it is instructive to clarify the connection between these different spin sectors in the QSL states of the isotropic Kitaev model.…”

“…Therefore, this bilayer model has an advantage in discussing how the QSL state for the S = 1/2 Kitaev model is connected to that for the S = 1 Kitaev model. By using numerical techniques, we study the bilayer Kitaev model to discuss the essence of the ground state properties in the generalized Kitaev model [23][24][25][26].…”