# Electrically Tunable Energy Bandgap in Dual-Gated Ultra-Thin Black Phosphorus Field Effect Transistors

## TL;DR

This paper demonstrates that the energy bandgap of few-layer black phosphorus can be continuously and reversibly tuned using a dual-gated field-effect transistor setup, enabling potential applications in infrared optoelectronics and thermal imaging.

## Contribution

We show a method to electrically tune the bandgap of few-layer black phosphorus in real time using dual-gated transistors, achieving a significant bandgap reduction.

## Key findings

- Bandgap reduction of 124 meV observed
- Bandgap tunability range from 0.10V/nm to 0.83V/nm
- Potential applications in infrared optoelectronics and thermoelectric devices

## Abstract

The energy bandgap is an intrinsic character of semiconductors, which largely determines their properties. The ability to continuously and reversibly tune the bandgap of a single device during real time operation is of great importance not only to device physics but also to technological applications. Here we demonstrate a widely tunable bandgap of few-layer black phosphorus (BP) by the application of vertical electric field in dual-gated BP field-effect transistors. A total bandgap reduction of 124 meV is observed when the electrical displacement field is increased from 0.10V/nm to 0.83V/nm. Our results suggest appealing potential for few-layer BP as a tunable bandgap material in infrared optoelectronics, thermoelectric power generation and thermal imaging.

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Source: https://tomesphere.com/paper/1703.08303