Optical Absorption and Emission from Wannier-Stark Spectra of Moiré Superlattices

Using a formalism based on the non-Abelian Berry connection, we explore quantum geometric signatures of Wannier-Stark spectra in two-dimensional superlattices. The Stark energy can be written as intraband Berry phases, while Zener tunneling is given by interband Berry connections. We suggest that the gaps induced by interband hybridization can be... Show more