Electronic and Transport Property of Phosphorene Nanoribbon

TL;DR

This study uses density functional theory and nonequilibrium Green's function methods to analyze the electronic and transport properties of phosphorene nanoribbons, revealing a giant Stark effect and proposing a high-performance PNR-based FET.

Contribution

It demonstrates the electric field modulation of band gaps and transport channels in phosphorene nanoribbons, introducing a novel PNR-based dual-gate FET with high on/off ratio.

Findings

Giant Stark effect enables insulator-metal transition in PNRs.

Transport channels are mainly in the interior, immune to edge defects.

Proposed PNR FET achieves on/off ratio of 10^3.

Abstract

By combining density functional theory and nonequilibrium Green's function, we study the electronic and transport properties of monolayer black phosphorus nanoribbons (PNRs). First, we investigate the band-gap of PNRs and its modulation by the ribbon width and an external transverse electric feld. Our calculations indicate a giant Stark effect in PNRs, which can switch on transport channels of semiconducting PNRs under low bias, inducing an insulator-metal-transition. Next, we study the transport channels in PNRs via the calculations of the current density and local electron transmission pathway. In contrast to graphene and MoS_2 nanoribbons, the carrier transport channels under low bias are mainly located in the interior of both armchair and zigzag PNRs, and immune to a small amount of edge defects. Lastly, a device of the PNR-based dual-gate feld-effect-transistor, with high on/off-ratio of 10^3, is proposed based on the giant electric feld tuning effect.