Broadband Bi₂O₂Se Photodetectors from Infrared to Terahertz

Abstract

2D Bi 2 O 2 Se has shown great potential in photodetector from visible to infrared (IR) owing to its high mobility, ambient stability, and layer-tunable bandgaps. However, for the terahertz (THz) band with longer wavelength and richer spectral information, there are few reports on the research of THz detection based on 2D materials. Herein, an antenna-assisted Bi 2 O 2 Se photodetector is constructed to achieve broadband photodetection from IR to THz ranges driven by multi-mechanism of electromagnetic waves to electrical conversion. The good tradeoff between the bandgap and high mobility results in a broad spectral detection. In the IR region, the nonequilibrium carriers result from photo-induced electron-hole pairs in the Bi 2 O 2 Se body. While in the THz region, the carriers are caused by the injected electrons from the metal electrodes by the electromagnetic-induced well. The Bi 2 O 2 Se photodetector achieves a broadband responsivity of 58 A W-1 at 1550 nm, 2.7 × 10 4 V W-1 at 0.17 THz, and 1.9 × 10 8 V W-1 at 0.029 THz, respectively. Surprisingly, an ultrafast response time of 476 ns and a quite low noise equivalent power of 0.2 pW Hz-1/2 are acquired at room temperature. Our researches exhibit promising prospects of Bi 2 O 2 Se in broadband detection, THz imaging, and ultrafast sensing.

Van der Waals Epitaxy of Bi2Te2Se/Bi2O2Se Vertical Heterojunction for High Performance Photodetector

“…[ 6–14 ] Extensive efforts have been paid to tailor the intrinsic material properties in Bi 2 O 2 Se based devices such as transistors, memristors, and photodetectors by optimizing material synthesis. [ 15–19 ] For example, Bi 2 O 2 Se based phototransistor has been achieved by He et al. with responsivity reaching 6.5 A W –1 and detectivity up to 8.3 × 10 11 Jones in the visible range.…”

Modulation of Ferroelectric and Optical Properties of La/Co-Doped KNbO3 Ceramics

“…In the past several decades, ferroelectric materials have become important candidates for photovoltaic, random-access memory and optoelectronic devices due to their inherent spontaneous polarization [ 1 , 2 , 3 , 4 , 5 , 6 ]. Among them, KNbO 3 (KNO) materials with excellent properties are a research hotspot.…”

Ultrabroadband Tellurium Photoelectric Detector from Visible to Millimeter Wave

“…In addition, we compared the polarization extinction ratio of Te and other 2D materials under different wavelengths/frequencies of light as shown in Table S2 (Supporting Information). [ 14 , 20 ]…”