Exact diagonalization approaches on a Kitaev spin liquid

Abstract

We reveal physical properties of Kitaev spin liquids exploiting exact diagonalization (ED) approach. With the ED method, we calculate physical observables, such as spin correlations and flux, which can characterize the spin liquid phase. We also show that other physical observables can detect quantum phase transitions in the spin models which include Kitaev interactions. Specfically, we discuss quantum phase transitions in the Kitaev-Heisenberg model and in a generic spin-1/2 model. So-called the $\Gamma$ spin interaction can trigger quantum phase transitions and difference phases can be distinguished by the energy profile features with varying magnetic field angles.