Room temperature gate-tunable negative differential resistance in MoS<inf>2</inf>/hBN/WSe<inf>2</inf> heterostructures

Abstract

Heterostructures based on transition metal dichalcogenides (TMDs) are attractive owing to their atomically thin nature and lack of dangling bonds, thereby enabling devices with abrupt junctions. Of particular interest are tunneling devices that manifest a negative differential resistance (NDR), which can pave the path to next generation, low-power tunnel field-effect transistors (TFETs). To date, NDR in TMD heterostructures has been observed only at low temperatures [1], and without gate control [2-4]. Here, we demonstrate dual-gated heterostructures of molybdenum disulfide (MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> )/hexagonal boron nitride (hBN)/tungsten diselenide (WSe <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> ) which show gate-tunable NDR with a peak-to-valley current ratio (PVCR) of 1.3 at 300 K, and increasing to 2.3 at 77 K.