Field-effect tunneling transistor based on vertical graphene   heterostructures
  We report a bipolar field effect tunneling transistor that exploits to advantage the low density of states in graphene and its one atomic layer thickness. Our proof-of-concept devices are graphene heterostructures with atomically thin boron nitride acting as a tunnel barrier. They exhibit room temperature switching ratios ~50, a value that can be enhanced further by optimizing the device structure. These devices have potential for high frequency operation and large scale integration. 
L. Britnell, R. V. Gorbachev, R. Jalil, B. D. Belle, F. Schedin, M. I.   Katsnelson, L. Eaves, S. V. Morozov, N. M. R. Peres...
cond-mat.mes-hall cond-mat.mtrl-sci