Field emission from two-dimensional GeAs

TL;DR

This study demonstrates that multilayer GeAs nanoflakes exhibit effective field emission properties, making them promising candidates for cold cathodes in vacuum electronic devices, with reproducible emission following Fowler-Nordheim behavior.

Contribution

It provides the first experimental evidence of field emission from two-dimensional GeAs nanoflakes and characterizes their electron emission properties for potential vacuum electronic applications.

Findings

Field emission with a turn-on field of ~80 V/μm

Current density exceeding 10 A/cm^2

Reproducible Fowler-Nordheim emission behavior

Abstract

GeAs is a layered material of the IV-V groups that is attracting growing attention for possible applications in electronic and optoelectronic devices. In this study, exfoliated multilayer GeAs nanoflakes are structurally characterized and used as the channel of back-gate field-effect transistors. It is shown that their gate-modulated p-type conduction is decreased by exposure to light or electron beam. Moreover, the observation of a field emission current demonstrates the suitability of GeAs nanoflakes as cold cathodes for electron emission and opens up new perspective applications of two-dimensional GeAs in vacuum electronics. Field emission occurs with a turn-on field of ~80 V/{\mu}m and attains a current density higher than 10 A/cm^2, following the general Fowler-Nordheim model with high reproducibility.