Trapped charge and contact barrier effects in room-temperature monolayer 2H-MoTe2 photodetectors
Abstract
Monolayer 2H-MoTe ₂ is a highly attractive material for near-infrared ultrathin photodetectors, though its reduced dimensionality introduces pronounced sensitivity to metal contacts and charge trapping processes. Here, we examine the device physics by correlating gate-dependent transport, effective trapped-charge density, and Schottky-barrier effects. The fabricated p-type device demonstrates distinct photoresponse across visible and near-infrared wavelengths (532, 633, and 785 nm). Under low-power of 785 nm illumination, the device reaches its highest measured responsivity of 112.73 mA W − 1 and a shot-noise-limited specific detectivity of 1.98 × 10⁹ Jones. Applying a negative gate bias increases p-type carrier accumulation and improves carrier extraction, giving a maximum EQE of 17.82% and an internal photocurrent gain of ~ 13.47 × 10 ³ . Taken together, these findings are consistent with a hybrid operating regime in which Schottky-barrier-limited transport contributes to suppressing the dark current, while trap-assisted carrier dynamics support enhanced responsivity and gain under low-power illumination.
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BibTeX
@article{abidi2026trapped,
title = {{Trapped charge and contact barrier effects in room-temperature monolayer 2H-MoTe2 photodetectors}},
author = {El Hadj Abidi and Krishna K. Yadav and Kenji Watanabe and Takashi Taniguchi and M. Dolores Merchán and Jesus Enrique Velázquez Pérez and Yahya M. Meziani and Enrique Diez and Mario Amado and Ana Pérez-Rodríguez},
journal = {Scientific Reports},
year = {2026},
month = oct,
doi = {10.1038/s41598-026-73426-6},
url = {https://www.nature.com/articles/s41598-026-73426-6},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Trapped charge and contact barrier effects in room-temperature monolayer 2H-MoTe2 photodetectors
AU - El Hadj Abidi
AU - Krishna K. Yadav
AU - Kenji Watanabe
AU - Takashi Taniguchi
AU - M. Dolores Merchán
AU - Jesus Enrique Velázquez Pérez
AU - Yahya M. Meziani
AU - Enrique Diez
AU - Mario Amado
AU - Ana Pérez-Rodríguez
PY - 2026
DA - 2026/10/04
JO - Scientific Reports
DO - 10.1038/s41598-026-73426-6
UR - https://www.nature.com/articles/s41598-026-73426-6
AB - Monolayer 2H-MoTe ₂ is a highly attractive material for near-infrared ultrathin photodetectors, though its reduced dimensionality introduces pronounced sensitivity to metal contacts and charge trapping processes. Here, we examine the device physics by correlating gate-dependent transport, effective trapped-charge density, and Schottky-barrier effects. The fabricated p-type device demonstrates distinct photoresponse across visible and near-infrared wavelengths (532, 633, and 785 nm). Under low-power of 785 nm illumination, the device reaches its highest measured responsivity of 112.73 mA W − 1 and a shot-noise-limited specific detectivity of 1.98 × 10⁹ Jones. Applying a negative gate bias increases p-type carrier accumulation and improves carrier extraction, giving a maximum EQE of 17.82% and an internal photocurrent gain of ~ 13.47 × 10 ³ . Taken together, these findings are consistent with a hybrid operating regime in which Schottky-barrier-limited transport contributes to suppressing the dark current, while trap-assisted carrier dynamics support enhanced responsivity and gain under low-power illumination.
SN - 2045-2322
ER -