Band Tunneling through Double Barrier in Bilayer Graphene

TL;DR

This paper analyzes electron tunneling through double barriers in bilayer graphene considering the full four-band spectrum, revealing resonance phenomena and multiple transmission modes depending on energy levels and barrier configurations.

Contribution

It provides a comprehensive calculation of transmission and conductance in bilayer graphene double barriers, including effects of full band spectrum and barrier asymmetry, which was not fully explored before.

Findings

Resonances occur for energies below interlayer coupling even with barriers

Four transmission modes are possible for energies above interlayer coupling

Double barrier geometry significantly affects transmission probabilities

Abstract

By taking into account the full four band energy spectrum, we calculate the transmission probability and conductance of electrons across symmetric and asymmetric double potential barrier with a confined interlayer potential difference in bilayer graphene. For energies less than the interlayer coupling \gamma_{1}, E<\gamma_1, we have one channel for transmission which exhibits resonances, even for incident particles with energies less than the strength of barriers, E < U_j, depending on the double barrier geometry. In contrast, for higher energies E > \gamma_{1}, we obtain four possible ways for transmission resulting from the two propagating modes. We compute the associated transmission probabilities as well as their contribution to the conductance, study the effect of the double barrier geometry.