Negative photoconductivity and hot-carrier bolometric detection of terahertz radiation in graphene-phosphorene hybrid structures

TL;DR

This paper investigates the negative photoconductivity in graphene-phosphorene hybrid structures and proposes hot-carrier bolometric detectors for terahertz radiation, demonstrating enhanced responsivity due to carrier heating and scattering effects.

Contribution

It introduces a novel approach to THz detection using graphene-phosphorene hybrid structures with gate-controlled negative conductivity for improved bolometric performance.

Findings

Negative photoconductivity observed in hybrid structures.

Proposed hot-carrier bolometric detectors with high responsivity.

Carrier heating enhances detection efficiency.

Abstract

We consider the effect of terahertz (THz) radiation on the conductivity of the ungated and gated graphene (G)-phosphorene (P) hybrid structures and propose and evaluated the hot-carrier uncooled bolometric photodetectors based on the GP-lateral diodes (GP-LDs) and GP-field-effect transistors (GP-FETs) with the GP channel. The operation of the GP-LDs and GP-FET photodetectors is associated with the carrier heating by the incident radiation absorbed in the G-layer due to the intraband transitions. The carrier heating leads to the relocation of a significant fraction of the carriers into the P-layer. Due to a relatively low mobility of the carriers in the P-layer, their main role is associated with a substantial reinforcement of the scattering of the carriers. The GP-FET bolometric photodetector characteristics are effectively controlled by the gate voltage. A strong negative conductivity of the GP-channel can provide much higher responsivity of the THz hot-carriers GP-LD and GP-FET bolometric photodetectors in comparison with the bolometers with solely the G-channels.