Theoretical studies of electronic transport in mono- and bi-layer phosphorene: A critical overview

TL;DR

This paper critically reviews theoretical models of electronic transport in phosphorene, highlighting uncertainties in predicted mobility and providing first-principles calculations that suggest lower performance than some earlier estimates.

Contribution

It offers a critical assessment of physical models used in predicting phosphorene's electronic transport, emphasizing the importance of model accuracy and presenting new first-principles high-field transport results.

Findings

Predicted low-field mobility varies widely depending on models used.

High-field mobility in multilayer phosphorene is strongly anisotropic and does not exceed ~30 cm² V⁻¹ s⁻¹.

More accurate models tend to predict lower performance, closer to the lower end of previous estimates.

Abstract

Recent $\textit{ab initio}$ theoretical calculations of the electrical performance of several two-dimensional materials predict a low-field carrier mobility that spans several orders of magnitude (from 26,000 to 35 cm$^{2}$ V$^{-1}$ s$^{-1}$, for example, for the hole mobility in monolayer phosphorene) depending on the physical approximations used. Given this state of uncertainty, we review critically the physical models employed, considering phosphorene, a group V material, as a specific example. We argue that the use of the most accurate models results in a calculated performance that is at the disappointing lower-end of the predicted range. We also employ first-principles methods to study high-field transport characteristics in mono- and bi-layer phosphorene. For thin multi-layer phosphorene we confirm the most disappointing results, with a strongly anisotropic carrier mobility that does not exceed $\sim$ 30 cm$^{2}$ V$^{-1}$ s$^{-1}$ at 300 K for electrons along the armchair direction.