Floquet engineering multi-channel Kondo systems

Floquet engineering is a powerful tool that consists of driving materials with periodic light. We show that Kondo impurities and Kondo lattices can be Floquet-tuned to generate multichannel Kondo physics even when the equilibrium case has a single channel. By changing the driving protocol, we can tune to two and three-channel multicritical points. These emergent channels are differentiated by symmetry, and their strength can be controlled by light polarization, frequency, and amplitude. In particular, unpolarized light, constructed by polarization averaging [1], can be useful for designing multichannel Kondo lattices that present Floquet-induced Kondo couplings not found in equilibrium. We first demonstrate our findings in a toy model on the square lattice. Then, we explore a realistic model for J=5/2 Ce ions in a tetragonal environment, which presents unique features arising from the spin-orbit coupling. The multichannel Kondo lattice can give rise to composite pair superconductivity, and we discuss how the nature of the superconductivity can be tuned, with application to the 115 materials.
[1] V. L. Quito and R. Flint, PRL 126, 177201 (2021)