High Optical Response of Niobium-Doped WSe<sub>2</sub>-Layered Crystals

oleh: Hung-Pin Hsu, Der-Yuh Lin, Jhin-Jhong Jheng, Pin-Cheng Lin, Tsung-Shine Ko

Format: Article
Diterbitkan: MDPI AG 2019-04-01

Deskripsi

The optical properties of WSe<sub>2</sub>-layered crystals doped with 0.5% niobium (Nb) grown by the chemical vapor transport method were characterized by piezoreflectance (PzR), photoconductivity (PC) spectroscopy, frequency-dependent photocurrent, and time-resolved photoresponse. With the incorporation of 0.5% Nb, the WSe<sub>2</sub> crystal showed slight blue shifts in the near band edge excitonic transitions and exhibited strongly enhanced photoresponsivity. Frequency-dependent photocurrent and time-resolved photoresponse were measured to explore the kinetic decay processes of carriers. Our results show the potential application of layered crystals for photodetection devices based on Nb-doped WSe<sub>2</sub>-layered crystals.