title: Creating stable Floquet-Weyl semimetals by laser-driving of 3D Dirac materials.
abstract: Tuning and stabilizing topological states, such as Weyl semimetals, Dirac semimetals or topological insulators, is emerging as one of the major topics in materials science. Periodic driving of many-body systems offers a platform to design Floquet states of matter with tunable electronic properties on ultrafast timescales. Here we show by first principles calculations how femtosecond laser pulses with circularly polarized light can be used to switch between Weyl semimetal, Dirac semimetal and topological insulator states in a prototypical three-dimensional (3D) Dirac material, Na3Bi. Our findings are general and apply to any 3D Dirac semimetal. We discuss the concept of time-dependent bands and steering of Floquet-Weyl points and demonstrate how light can enhance topological protection against lattice perturbations. This work has potential practical implications for the ultrafast switching of materials properties, such as optical band gaps or anomalous magnetoresistance.
authors.affiliation: Nano-Bio Spectroscopy Group and ETSF, Universidad del País Vasco, CFM CSIC-UPV/EHU, San Sebastián 20018, Spain.
authors.forename: Hannes
authors.initials: H
authors.lastname: Hübener
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter and Center for Free Electron Laser Science, Hamburg 22761, Germany.
authors.forename: Michael A
authors.identifier: 0000-0002-7946-0282
authors.initials: MA
authors.lastname: Sentef
authors.affiliation: Nano-Bio Spectroscopy Group and ETSF, Universidad del País Vasco, CFM CSIC-UPV/EHU, San Sebastián 20018, Spain.|Dipartimento di Fisica e Chimica, Universitá degli Studi di Palermo, Via Archirafi 36, I-90123, Palermo, Italy.
authors.forename: Umberto
authors.initials: U
authors.lastname: De Giovannini
authors.affiliation: Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202, USA.
authors.forename: Alexander F
authors.identifier: 0000-0002-5426-5181
authors.initials: AF
authors.lastname: Kemper
authors.affiliation: Nano-Bio Spectroscopy Group and ETSF, Universidad del País Vasco, CFM CSIC-UPV/EHU, San Sebastián 20018, Spain.|Max Planck Institute for the Structure and Dynamics of Matter and Center for Free Electron Laser Science, Hamburg 22761, Germany.
authors.forename: Angel
authors.identifier: 0000-0003-2060-3151
authors.initials: A
authors.lastname: Rubio