Mechanical Strain Effects on Black Phosphorus Nanoresonators

TL;DR

This study uses molecular dynamics to explore how mechanical strain influences the resonant frequency and quality factor of black phosphorus nanoresonators, revealing anisotropic behavior and strain-induced enhancements.

Contribution

It provides the first detailed analysis of strain effects on black phosphorus nanoresonators, highlighting anisotropic resonant properties and strain-tuning of quality factors.

Findings

Resonant frequency is highly anisotropic due to puckered structure.

Quality factor is higher in the armchair direction than in zigzag at room temperature.

Applying tensile strain can more than double the quality factor, with an upper limit due to nonlinear effects.

Abstract

We perform classical molecular dynamics to investigate the effects of mechanical strain on single-layer black phosphorus nanoresonators at different temperatures. We find that the resonant frequency is highly anisotropic in black phosphorus due to its intrinsic puckered configuration, and that the quality factor in the armchair direction is higher than in the zigzag direction at room temperature. The quality factors are also found to be intrinsically larger than graphene and MoS2 nanoresonators. The quality factors can be increased by more than a factor of two by applying tensile strain, with uniaxial strain in the armchair direction being most effective. However, there is an upper bound for the quality factor increase due to nonlinear effects at large strains, after which the quality factor decreases. The tension induced nonlinear effect is stronger along the zigzag direction, resulting in a smaller maximum strain for quality factor enhancement.