Helical superconducting edge modes from pseudo-Landau levels in graphene

We explore Andreev states at the interface of graphene and a superconductor for a uniform pseudomagnetic field. Near the zeroth-pseudo-Landau level, we find a topological transition as a function of applied Zeeman field, at which a gapless helical mode appears. This one-dimensional mode is protected from backscattering as long as intervalley and spin-flip scattering are suppressed. We discuss a possible experimental platform to detect this gapless mode based on strained suspended membranes on a superconductor, in which dynamical strain causes charge pumping.