Phosphorene as a nanoelectromechanical material

TL;DR

This study uses density functional simulations and transport theory to explore how mechanical strain affects the electronic and charge transport properties of phosphorene, revealing its potential for high-pressure nanoelectromechanical sensors.

Contribution

It demonstrates the strain-dependent electronic and transport properties of phosphorene, highlighting its high piezoconductance sensitivity and potential for nanoelectromechanical applications.

Findings

Piezoconductance gauge factor increases from 46 to 220 with strain.

Strain enhances intraplanar interactions and affects band structure.

Transport is mainly through chemical bonds and hopping.

Abstract

Based on density functional simulations combined with the Landauer transport theory, the mechanical strain impacts on the chemical bonds of phosphorene and their effects on the electronic properties are studied. Moreover, the effect of the tensile strain along the zigzag direction on the charge transport properties of a two-terminal phosphorene device is evaluated. Enhancement of the intraplanar interactions, in particular between the next-nearest neighbors in strained phosphorene, is found to be essential in the band-structure evolution. The charge transport analyzing shows that phosphorene has a strong piezoconductance sensitivity, which makes this material highly desirable for high-pressure nanoelectromechanical applications. The piezoconductance gauge factor increases by strain from 46 in 5% tension to 220 in 12% tension, which is comparable to state-of-the-art silicon strain sensors. The transmission pathways monitor the current flowing in terms of the chemical bonds and hopping, however, the transport mostly arises from the charge transferring through the chemical bonds. The strong anisotropy in the transport properties along zigzag and armchair directions is observed.