Polarity-dependent twist-controlled resonant tunneling device based on few-layer WSe_{2}

Few-layer (FL) transition metal dichalcogenides have been found to exhibit discrete subbands, called van der Waals quantum well (vdWQW) states, resulting from out-of-plane quantum confinement. In this study, we reveal the twisted-resonant tunneling characteristics of a vdWQW device using a three-layer (3L) WSe_{2}/h-BN/3L-WSe_{2} junction with different twist angles θ_{tunnel} between the two 3L WSe_{2} flakes. Using an ambipolar graphene contact to WSe_{2}, two primary vdWQW states of 3L WSe_{2} located in the conduction band (CB) and valence band (VB) were investigated. We found that while the current peak positions due to the electron resonant tunneling between the CB-QW states significantly change with θ_{tunnel} having a periodicity of 60^{∘}, the hole resonant tunneling between the VB-QW states exhibits no θ_{tunnel} dependence; these are due to different angular dispersions of two vdWQWs. The results highlight the different twistronic properties of CB and VB vdWQWs in FL WSe_{2}.