Driving a two-dimensional Mott insulator with circularly polarized light breaks time-reversal and inversion symmetry, which induces an optically-tunable synthetic scalar spin chirality interaction in the effective low-energy spin Hamiltonian. Here, we show that this mechanism can stabilize topological magnon excitations in honeycomb ferromagnets and in optical lattices. We find that the irradiated quantum magnet is described by a Haldane model for magnons that hosts topologically-protected edge modes. We study the evolution of the magnon spectrum in the Floquet regime and via time propagation of the magnon Hamiltonian for a slowly varying pulse envelope. Compared to similar but conceptually distinct driving schemes based on the Aharanov-Casher effect, the dimensionless light-matter coupling parameter $\lambda = eEa/\hbar\omega$ at fixed electric field strength is enhanced by a factor $\sim 10^5$. This increase of the coupling parameter allows to induce a topological gap of the order of $\Delta \approx 2$ meV with realistic laser pulses, bringing an experimental realization of light-induced topological magnon edge states within reach.
Cited by 1
Hiroomi Chono et al., Laser-induced topological
-wave superconductivity in bilayer transition metal dichalcogenides
Phys. Rev. B 102, 174508 (2020) [Crossref]
Authors / Affiliations: mappings to Contributors and OrganizationsSee all Organizations.
- 1 Emil Vinas Boström,
- 2 Martin Claassen,
- 1 James McIver,
- 1 Gregor Jotzu,
- 1 2 Angel Rubio,
- 1 3 Michael Sentef
- 1 Max-Planck-Institut für Struktur und Dynamik der Materie / Max Planck Institute for the Structure and Dynamics of Matter [MPSD]
- 2 Flatiron Institute
- 3 Universität Bremen / University of Bremen