Gate-tunable self-driven photodetector based on asymmetric monolayer WSe2 channel

Self-Powered Programmable van der Waals Photodetectors with Nonvolatile Semifloating Gate

“…The photovoltaic response is characterized by attributes such as low-power consumption, rapid response, and low dark current. 6−8 This behavior is commonly attributed to the built-in electric field within various junctions, including p + -p, p-n, n + -n, and Schottky junctions, which are typically fabricated through processes such as chemical doping, 9,10 materials stacking, 11,12 epitaxial growth, 13,14 local split gating, 15−19 strain engineering, 20,21 or asymmetric contacting. 22−25 Distinguished by the volatile or nonvolatile nature of these junctions, two strategies involving continuous and pulsed voltage application are typically employed to tune the photovoltaic photoresponse, enabling transitions from negative to positive responses.…”

“…Additionally, R and D* align closely with the calculated absorbance of 6.3 nm MoTe 2 (Figure S8) using the Lambert−Beer law and the reported experimental data of trilayer MoTe 2 , 36 which can potentially be further enhanced through optical or plasmonic resonances. 21,49,50 Tunable photoresponses can be achieved by varying the pulsed gate voltage. Figure 5a illustrates that the photocurrent increases from −0.096 to 0.68 nA under 532 nm illumination (laser power density 2.09 mW/cm 2 ) as V cg-pulse increases from −60 to 60 V (in 10 V increments).…”

“…This surge in attention is particularly evident with the advancement of programmable , and neuromorphic − optoelectronics. The photovoltaic response is characterized by attributes such as low-power consumption, rapid response, and low dark current. − This behavior is commonly attributed to the built-in electric field within various junctions, including p + -p, p-n, n + -n, and Schottky junctions, which are typically fabricated through processes such as chemical doping, , materials stacking, , epitaxial growth, , local split gating, − strain engineering, , or asymmetric contacting. − Distinguished by the volatile or nonvolatile nature of these junctions, two strategies involving continuous and pulsed voltage application are typically employed to tune the photovoltaic photoresponse, enabling transitions from negative to positive responses. For example, in certain narrow-bandgap 2D semiconductor-based heterojunctions (e.g., BP/MoTe 2 , PdSe 2 /MoTe 2 , AsP/MoS 2 ) and the configuration of ambipolar 2D semiconductor-based homojunctions (e.g., BP, WSe 2 , MoTe 2 ), the band alignment can be effectively modulated through continuous global gating and split gating, respectively, resulting in gate-tunable photoresponse.…”

MoS2 / WS2 Nanosheets and Quantum Dots for Sensing Hemin and Fabrication of Self-Powered Photodetectors

“…24 Furthermore, their tunable band gap is complemented by strong photoluminescence and high exciton binding energy, positioning them as promising candidates for a wide range of optoelectronic devices such as solar cells, 25 light-emitting diodes, 26 photodetectors, 27 and phototransistors. 28 However, the conventional routes for preparing TMDC are not straightforward. For example, chemical vapor deposition is a very sophisticated setup and employs toxic precursors leading to safety concerns and operational complexities.…”

Asymmetrically Contacted Tellurium Short‐Wave Infrared Photodetector with Low Dark Current and High Sensitivity at Room Temperature

“…[37] v) The fifth method is to use asymmetric electrical contact to obtain self-powered photoresponse, where the dark current can be reduced to zero theoretically for the lack of external power supply. Asymmetric electrical contact can be realized by electrodes with asymmetric work function, [38][39][40] asymmetric van der Waals contacts, [41][42][43] asymmetric channel widths, [44,45] etc. Compared with other strategies, this method is much more convenient and energy efficient.…”