High-Responsivity Photodetection by Self-Catalyzed Phase-Pure P-GaAs Nanowire

TL;DR

This paper reports the development of self-catalyzed phase-pure P-GaAs nanowires with high responsivity and detectivity for photodetection, achieved by eliminating defects and stacking faults that impair device performance.

Contribution

It introduces a novel self-catalyzed growth method for pure-ZB GaAs nanowires, leading to superior optoelectronic device performance compared to previous nanowire photodetectors.

Findings

High photoresponsivity of 1.45 x 10^5 A/W at room temperature

Exceptional specific detectivity of 1.48 x 10^14 Jones

Elimination of stacking faults enhances device performance

Abstract

Defects are detrimental for optoelectronics devices, such as stacking faults can form carrier-transportation barriers, and foreign impurities (Au) with deep-energy levels can form carrier traps and non-radiative recombination centers. Here, we first developed self-catalyzed p-type GaAs nanowires (NWs) with pure zinc blende (ZB) structure, and then fabricated photodetector made by these NWs. Due to absence of stacking faults and suppression of large amount of defects with deep energy levels, the photodetector exhibits room-temperature high photo responsivity of 1.45 x 105 A W^-1 and excellent specific detectivity (D*) up to 1.48 x 10^14 Jones for low-intensity light signal of wavelength 632.8 nm, which outperforms previously reported NW-based photodetectors. These results demonstrate that these self-catalyzed pure-ZB GaAs NWs to be promising candidates for optoelectronics applications.