Physics Chat
Effect of vortex light beams on Dirac and Weyl materials
Speaker: Kyle Netherwood ()
Date: Wednesday 12 February 2025
Time: 14:00
Venue: N/1.32
A previous theoretical study [1] has shown that vortex light beams incident on massive Dirac materials create a topologically insulating phase with a number of fermionic edge states equal to the orbital angular momentum of the light. In this talk, we discuss an extension of this study to massless Dirac semimetals and tiltless Weyl semimetals. Treating the time dependence of the light using Floquet theory, we derive a Bogoliubov-de Gennes equation for each case which are diagonalised using the Bessel decomposition. The result of these methods are a 2D quasi-energy spectrum for the Dirac case which demonstrates the topological insulation and a 3D quasi-energy spectrum for the Weyl case which is expected to feature topologically protected Weyl nodes.
References: [1] Massaro, L.I., Meese, C., Sandler, N.P. and Asmar, M.M., 2024. Photo-induced Multiply Quantized Vortex States in Dirac-like Materials. arXiv preprint arXiv:2404.09086.