Gate-Tunable Resonant Tunneling in Double Bilayer Graphene   Heterostructures
  We demonstrate gate-tunable resonant tunneling and negative differential resistance in the interlayer current-voltage characteristics of rotationally aligned double bilayer graphene heterostructures separated by hexagonal boron-nitride (hBN) dielectric. An analysis of the heterostructure band alignment using individual layer densities, along with experimentally determined layer chemical potentials indicates that the resonance occurs when the energy bands of the two bilayer graphene are aligned. We discuss the tunneling resistance dependence on the interlayer hBN thickness, as well as the resonance width dependence on mobility and rotational alignment. 
Babak Fallahazad, Kayoung Lee, Sangwoo Kang, Jiamin Xue, Stefano   Larentis, Christopher Corbet, Kyounghwan Kim, Hema C. P. ...
cond-mat.mes-hall cond-mat.str-el