Abstract:
In this talk, I will delve into two new topics in the field of two-dimensional (2D) materials physics: the impact of strong laser illumination on materials with an existing topological phase, and the interaction between electrons and chiral phonons. The first part of my talk will explore how intense laser illumination can be used to generate tunable spin-polarized photocurrents in the presence of spin-orbit interaction ^[1], and how it can cause a switch in chirality of the edge states in graphene when in the quantum Hall regime ^[2]. In the second part, I will tackle the intriguing issue of electron-phonon interactions with chiral phonons. The theoretical prediction ^[3] and subsequent observation ^[4] of chiral phonons in 2D materials has added a fresh dimension to this persistent challenge. I will present an overview of this area, emphasizing our recent findings on the effects of electron-chiral phonon interactions in 2D materials ^[5-7]. By using a non-perturbative solution, we demonstrate that chiral phonons trigger inelastic Umklapp processes, leading to peculiar co-propagating edge states. Our results hint on the possibility of having new electron-phonon states of matter.

^[1] M. Berdakin, E. A. Rodriguez-Mena, and L. E. F. Foa Torres, Nano Letters 21, 3177 (2021).
^[2] A. Huaman, L. E. F. Foa Torres, C. A. Balseiro, L. E. F. Foa Torres, Phys. Rev. Research 3, 013201 (2021).
^[3] L. Zhang and Q. Niu, Phys. Rev. Lett. 115, 115502 (2015).
^[4] H. Zhu et al., Science 359, 579 (2018).
^[5] J. Medina Dueñas, H. L. Calvo, L. E. F. Foa Torres, Phys. Rev. Lett. 128, 066801 (2022).
^[6] J. Mella, H. L. Calvo, L. E. F. Foa Torres, to appear.
^[7] For related research see https://www.foatorres.com/