Double bilayer graphene-WSe2 resonant tunneling heterostructures with high interlayer current densities and peak-to-valley ratios

Van der Waals heterostructures consisting of two dimensional (2D) materials have been a topic of great interest recently due to their diverse electrical characteristics and device applications. One property that has attracted attention because of potential device applications is tunneling between two 2D atomic layers separated by a barrier, which may possess gate tunable negative differential resistance (NDR) [1, 2]. This can be achieved experimentally if the tunneling between the 2D layers conserves both energy and momentum [2]. We present here resonant tunneling between two bilayer graphene crystals separated by a WSe
₂
tunnel barrier, which shows gate-tunable NDR in the interlayer current-voltage characteristics, with large interlayer peak current densities and peak-to-valley ratios.