Observing Topological Phase Transitions with High Harmonic Generation
Alexis Chacón, Wei Zhu, Shane P. Kelly, Alexandre Dauphin, Emilio Pisanty, Antonio Picón, Christopher Ticknor, Marcelo F. Ciappina, Avadh Saxena and Maciej Lewenstein
Received Date: 29th August 18
Topological materials are of interest to both fundamental sciences and advanced technologies, because topological states are robust with respect to perturbations and dissipation. Experimental detection of topological invariants is thus in great demand, but is extremely challenging. Ultrafast laser-matter interactions, leading to high harmonic generation (HHG) or laser-induced electron diffraction (LIED), were proposed several years ago to explore the structural and dynamical properties of various matter targets. Here, we show that HHG can be used to detect topological phases and phase transitions in the paradigmatic Haldane model. Intra-band and inter-band currents for parallel and perpendicular emission with respect to a linear-polarized laser-field are studied via our theoretical approach. We find evidence to show that even and odd harmonics as well as their emitted intensities are sensitive to crossing a topological phase boundary while the inversion and time-reversal fundamental symmetries are broken in the medium. Our findings pave the way to understand fundamental questions about the ultrafast electron-hole pair dynamics in topological materials via HHG.
Read in full at arXiv.
This is an abstract of a preprint hosted on an independent third party site. It has not been peer reviewed but is currently under consideration at Nature Communications.