Berry Curvature Spectroscopy from Bloch Oscillations

We demonstrate that the Berry curvature of an isolated Bloch miniband in two-dimensional superlattices can be probed by the dressed linear optical response when a uniform static field is applied to the system. In particular, when the static field is sufficiently strong such that full Bloch oscillations occur before the crystal momentum relaxes to equilibrium, the optical response of the dressed system becomes resonant at the Bloch frequencies. The latter are in the THz regime when the superlattice periodicity is of the order of 10 nm. Using a band-projected semiclassical theory, we define a dressed optical conductivity and find that the height of the resonances in the dressed Hall conductivity are proportional to the Fourier components of the Berry curvature. We illustrate our results with a low-energy model on an effective honeycomb lattice.