



01895nas a2200169   4500008004100000245007600041210006900117260001400186520129700200653002701497653005601524653004401580100002101624700002201645700002101667856003701688       2022                        eng d00aOptical conductivity and orbital magnetization of Floquet vortex states0 aOptical conductivity and orbital magnetization of Floquet vortex  c4/20/20223 a<p>Motivated by recent experimental demonstrations of Floquet topological insulators, there have been several theoretical proposals for using structured light, either spatial or spectral, to create other properties such as flat band and vortex states. In particular, the generation of vortex states in a massive Dirac fermion insulator irradiated by light carrying nonzero orbital angular momentum (OAM) has been proposed [Kim et al. Phys. Rev. B 105, L081301(2022)]. Here, we evaluate the orbital magnetization and optical conductivity as physical observables for such a system. We show that the OAM of light induces nonzero orbital magnetization and current density. The orbital magnetization density increases linearly as a function of OAM degree. In certain regimes, we find that orbital magnetization density is independent of the system size, width, and Rabi frequency of light. It is shown that the orbital magnetization arising from our Floquet theory is large and can be probed by magnetometry measurements. Furthermore, we study the optical conductivity for various types of electron transitions between different states such as vortex, edge, and bulk that are present in the system. Based on conductance frequency peaks, a scheme for the detection of vortex states is proposed.</p>10aFOS: Physical sciences10aMesoscale and Nanoscale Physics (cond-mat.mes-hall)10aOther Condensed Matter (cond-mat.other)1 aAhmadabadi, Iman1 aDehghani, Hossein1 aHafezi, Mohammad  uhttps://arxiv.org/abs/2204.09488