Floquet Engineering of Interlayer Exchange Interaction in a Rashba Magnetic Multilayer

Rashba semiconductors, such as bismuth tellurohalides (e.g., BiTeI), exhibit a giant spin-orbit coupling arising from the lack of crystal inversion symmetry. On the other hand, periodic driving by light provides a versatile tool to dynamically control material properties. In this work, we study the effects of light irradiation on the electronic and spin properties of the Rashba semiconductor BiTeI. In the high-frequency limit, we analyze the influence of Floquet driving on its low-energy quasiparticle spectrum. In magnetic multilayers, the long-range nature of the indirect exchange interaction mediated by the spacer material provides a useful mechanism for transfer of spin-encoded information. We therefore propose a Rashba magnetic multilayer, i.e., a magnetic multilayer formed by BiTeI sandwiched between two ferromagnetic layers, and investigate the effects of Floquet drive on this system. We present our results on the light-driven noncollinear exchange interaction in this irradiated multilayer and elucidate the roles of photon-dressed bands and photo-modulation of spin textures.