Optically Probing Tunable Band Topology in Atomic Monolayers

• DOI: 10.1103/physrevlett.125.157402
• Publication Date: 2020-10-08T20:05:56Z
• Authors: Gaofeng Xu; Tong Zhou; Benedikt Scharf; Igor Žutić
• Keywords: Hamiltonian (control theory); Helicity; Realization (probability)

In many atomically thin materials their optical absorption is dominated by excitonic transitions. It was recently found that selection rules in these are influenced the band topology near valleys. We propose gate-controlled ordering a single atomic monolayer, through changes valley winding number and transitions, can be probed helicity-resolved photoluminescence. This predicted tunable confirmed combining an effective Hamiltonian Bethe-Salpeter equation for accurate description of excitons, with first-principles calculations suggesting its realization Sb-based monolayers.