Comparing the influence of Floquet dynamics in various Kitaev-Heisenberg materials

TL;DR

This paper explores Floquet engineering in Kitaev materials, deriving effective Hamiltonians and analyzing how light frequency and polarization can tune magnetic interactions, with implications for controlling quantum magnetic states.

Contribution

It provides a detailed analysis of Floquet effects in three Kitaev materials, including effective Hamiltonian derivation and the impact of light parameters on magnetic couplings.

Findings

Third-neighbor Heisenberg coupling $J_3$ is highly tunable by circularly polarized light.

Materials with stronger Hund's-rule coupling exhibit less heating under Floquet driving.

Linear polarized light can selectively tune specific bond directions.

Abstract

In this paper we examine the possibility of Floquet engineering in the three candidate Kitaev materials $\mathrm{Na}_2\mathrm{IrO}_3$, $\alpha$-$\mathrm{Li}_2\mathrm{IrO}_3$ and $\alpha$-$\mathrm{RuCl}_3$. We derive an effective Floquet Hamiltonian and give an approximation for heating processes arising from doublon holon propagation.This suggests that compounds with stronger Hund's-rule coupling are less prone to heating. We then investigate the impact of light frequency and amplitude on magnetic interaction terms up to third-nearest-neighbor and find that third-neighbor Heisenberg coupling $J_3$ is very susceptible to tuning by circularly polarized light. Finally, we discuss uses of linear polarized light in selectively tuning single bond directions.