Phonon Dynamics in the Chiral Kitaev Spin Liquid

Abstract

We investigate the effect of a magnetic field on the extended Kitaev spin liquid state through phonon dynamics. Using a constrained fermionic self-consistent mean field method, we analyze the quantum spin liquid (QSL) ground state for the extended Kitaev model with both the Zeeman term and the perturbative three-spin interaction term $\kappa$. Our results demonstrate the dependence of the stability of the Kitaev QSL state on the field direction, consistent with findings in the literature. Additionally, we calculate the phonon dynamics for acoustic phonons coupled to the Majorana fermion excitations of the Kitaev spin liquid state, discussing the temperature and field evolution of these quantities.