Enhancing Performance of a GaAs/AlGaAs/GaAs Nanowire Photodetector Based on the Two-Dimensional Electron–Hole Tube Structure

Abstract

Here, we design and engineer an axially asymmetric GaAs/AlGaAs/GaAs (G/A/G) nanowire (NW) photodetector that operates efficiently at room temperature. Based on the I-type band structure, the device can realize a two-dimensional electron–hole tube (2DEHT) structure for the substantial performance enhancement. The 2DEHT is observed to form at the interface on both sides of GaAs/AlGaAs barriers, which constructs effective pathways for both electron and hole transport in reducing the photocarrier recombination and enhancing the device photocurrent. In particular, the G/A/G NW photodetector exhibits a responsivity of 0.57 A/W and a detectivity of 1.83 × 1010 Jones, which are about 7 times higher than those of the pure GaAs NW device. The recombination probability has also been significantly suppressed from 81.8% to 13.2% with the utilization of the 2DEHT structure. All of these can evidently demonstrate the importance of the appropriate band structure design to promote photocarrier generation, separation, and collection for high-performance optoelectronic devices.

Universal Strategy Integrating Strain and Interface Engineering to Drive High‐Performance 2D Material Photodetectors

“…Upon comparison with the f‐In 2 Se 3 device, we find that the SS‐In 2 Se 3 device can effectively suppress the dark current (Figure S3, Supporting Information) and enhance the photocurrent ( I ph = I light − I dark , Figure S4, Supporting Information) at a bias of 1 V. In addition, as shown in Figure S4, Supporting Information, I ph in the SS‐In 2 Se 3 device exhibits saturation under lower bias voltages, which indicates that the suspended and strained structure can significantly improve the collection of photogenerated carriers. [ 36 ] To better evaluate the photodetection performance, we next calculated the key indicators of the on/off ratio, responsivity ( R ), detectivity ( D *), and response rate (detailed calculation formulas are available in Note S2, Supporting Information). Figure 4c compares the on/off ratios of the two constructed devices under various light intensities at a bias of 1 V. The on/off ratio of both photodetectors increases with increasing light intensity.…”

A High‐Performance and Long‐Term Air‐Stable CH3NH3PbI3/C8BTBT Heterojunction Photodetector Fabricated via Chemical Vapor Deposition

“…[ 1–3 ] Conventional photodetectors are mainly made of inorganic materials such as Si and direct‐bandgap II–VI/III–V semiconductor materials. [ 4–6 ] In recent years, metal–halide perovskites with advantages of strong light absorption, low defect density, high carrier mobility, long carrier lifetime, and adjustable bandgap are suitable for the application in the field of photovoltaics. [ 7–10 ] In addition, organic–inorganic hybrid perovskites (e.g., MAPbI 3 ) have emerged as a promising class of potentially revolutionary optoelectronic semiconductors for applications in photodetectors, solar cells, light‐emitting diodes (LEDs), and lasers.…”

Design, preparation, and characterization of CS/PVA/SA hydrogels modified with mesoporous Ag2O/SiO2 and curcumin nanoparticles for green, biocompatible, and antibacterial biopolymer film

“…[1][2][3][4][5] Various polymers of natural and synthetic origin are used to make hydrogels. [6][7][8][9][10] Physical hydrogels are formed through weak secondary forces and chemical hydrogels are created by covalent forces. [11][12][13] Swelling, mechanical properties, and biological properties are among the most important properties of hydrogels, each of which can affect the structure and morphology of the hydrogel.…”