Resonant Tunneling and Intrinsic Bistability in Twisted Graphene Structures

We propose a novel mechanism for intrinsic bistability in van der Waals heterostructures formed by multiple twisted graphene layers. Bistability in these systems originates from resonant tunneling and charge coupling between different graphene layers. These characteristics, governed by the Dirac-like spectrum and Moir\'{e} periodicity of the tunneling Hamiltonian, allow multiple stable states in the sequential tunneling regime. In the bistability region, an intermediate electrically decoupled graphene layer can, for the same external bias, be either in a resonant or non-resonant state with respect to the top/bottom layer. Features of interest, such as resonant tunneling, negative differential resistance and bistability, are controlled by geometric device parameters easily accessible in experiments, namely the twist angle and the interlayer distances.