Abstract
A theory is developed for calculating vertical tunneling current between two sheets of bilayer graphene separated by a thin, insulating layer of hexagonal boron nitride, neglecting many-body effects. Results are presented using physical parameters that enable comparison of the theory with recently reported experimental results. Observed resonant tunneling and negative differential resistance in the current–voltage characteristics are explained in terms of the electrostatically-induced band gap, gate voltage modulation, density of states near the band edge, and resonances with the upper sub-band. These observations are compared to ones from similar heterostructures formed with monolayer graphene.
Highlights
A theory is developed for calculating vertical tunneling current between two sheets of bilayer graphene separated by a thin, insulating layer of hexagonal boron nitride, neglecting many-body effects
An even more intriguing distinction with monolayer graphene (MLG) is that, under the influence of external fields, the band structure of bilayer graphene (BLG) near the charge neutrality point becomes quartic, changing from semi-metallic to semiconducting as a small band gap is induced.[3–5]. This tunability of the band gap can be exploited by introducing gates, doping, and interactions with substrate materials in electronic devices based on BLG.[6–8]
We consider these effects and others in a 2D to 2D resonant tunneling device composed of two sheets of BLG separated by a thin, insulating layer of hexagonal boron nitride (h-BN)
Summary
A theory is developed for calculating vertical tunneling current between two sheets of bilayer graphene separated by a thin, insulating layer of hexagonal boron nitride, neglecting many-body effects. In contrast to the theory for MLG devices, for BLG this δ-function must be evaluated using the quartic dispersion relation in order to capture band-gap and higher sub-band effects.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
