Negative differential resistances with back gate-controlled lowest operation windows in graphene double barrier resonant tunneling diodes

TL;DR

This paper theoretically explores negative differential resistance in graphene-based double barrier resonant tunneling diodes, highlighting how a back gate can control the operation window and enhance performance.

Contribution

It demonstrates that the NDR feature depends on structural parameters and can be tuned via a back gate, with the lowest NDR window being nearly structure-free.

Findings

NDR appears only with specific structural parameters for massless Dirac Fermions.

The peak-to-valley current ratio can be exponentially increased by a tunable band gap.

The lowest NDR operation window is controllable mainly by a back gate.

Abstract

We theoretically investigate negative differential resistance (NDR) of massless and massive Dirac Fermions in double barrier resonant tunneling diodes based on sufficiently short and wide graphene strips. The current-voltage characteristics calculated in a rotated pseudospin space show that, the NDR feature only presents with appropriate structural parameters for the massless case and the peak-to-valley current ratio can be enhanced exponentially by a tunable band gap. Remarkably, the lowest NDR operation window is nearly structure-free and can be almost solely controlled by a back gate, which may have potential applications in NDR devices with the operation window as a crucial parameter.