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arXiv · 1210.2033

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

Yu Song·Han-Chun Wu·Yong Guo
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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.

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Yu Song, Han-Chun Wu, Yong Guo. 2012-10-07. Negative differential resistances with back gate-controlled lowest operation windows in graphene double barrier resonant tunneling diodes. https://doi.org/10.1063/1.4794952

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