Photogating in few-layered ReS<sub>2</sub> Phototransistors
ORAL
Abstract
Two-dimensional layered transition metal dichalcogenides (TMDs) have shown much promise due to their remarkable electro-optical properties and potential uses as photodetectors. We measured the photoconductivity on few-layered (≤ 10 layers) ReS2 field-effect transistors (FET) in both two-terminal and four-terminal configurations using a 532 nm excitation source. The photocurrent was measured as a function of incident optical power, drain-source voltage, and back-gate voltage. We obtained a maximum responsivity (R) of 45 A/W corresponding to an external quantum efficiency (EQE) of ~10,500% in the four-terminal configuration. We also observed photogating, in which varying the incident optical power shifts the FET threshold voltage. We will present our results and discuss their implications for the presence of trap states and the effect on the overall channel carrier density.
*This work was supported by NSF DMR-1229217 and the Army Research Office through the MURI grant W911NF-11-1-0362.
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Presenters
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Carlos Garcia
- Physics, Florida State University; National High Magnetic Field Lab
- 1800 E. Paul Dirac Drive, National High Magnetic Field Laboratory, Natl High Magnetic Field Lab