Highly Sensitive and Ultra-Broadband VO2(B) Photodetector Dominated by Bolometric Effect

Yujing Zhang; Ximiao Wang; Yang Zhou; Haojie Lai; Pengyi Liu; Huanjun Chen; Xiaomu Wang; Weiguang Xie

doi:10.1021/acs.nanolett.1c04393

Highly Sensitive and Ultra-Broadband VO₂(B) Photodetector Dominated by Bolometric Effect

Nano Lett. 2022 Jan 12;22(1):485-493. doi: 10.1021/acs.nanolett.1c04393. Epub 2021 Dec 30.

Authors

Yujing Zhang¹, Ximiao Wang², Yang Zhou¹, Haojie Lai¹, Pengyi Liu^{1

3}, Huanjun Chen², Xiaomu Wang⁴, Weiguang Xie^{1

3}

Affiliations

¹ Siyuan Laboratory, Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy Materials, Department of Physics, Jinan University, Guangzhou, Guangdong 510632, People's Republic of China.
² State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou, Guangdong 510275, People's Republic of China.
³ Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Jinan University, Guangzhou, Guangdong 510632, People's Republic of China.
⁴ School of Electronic Science and Technology, Nanjing University, Nanjing, Jiangsu 210093, People's Republic of China.

PMID: 34967644
DOI: 10.1021/acs.nanolett.1c04393

Abstract

In this study, Wadsley B phase vanadium oxide (VO₂(B)) with broad-band photoabsorption ability, a large temperature coefficient of resistance (TCR), and low noise was developed for uncooled broad-band detection. By using a freestanding structure and reducing the size of active area, the VO₂(B) photodetector shows stable and excellent performances in the visible to the terahertz region (405 nm to 0.88 mm), with a peak TCR of -4.77% K^-1 at 40 °C, a peak specific detectivity of 6.02 × 10⁹ Jones, and a photoresponse time of 83 ms. A terahertz imaging ability with 30 × 30 pixels was demonstrated. Scanning photocurrent imaging and real-time temperature-photocurrent measurements confirm that a photothermal-type bolometric effect is the dominating mechanism. The study shows the potential of VO₂(B) in applications as a new type of uncooled broad-band photodetection material and the potential to further raise the performance of broad-band photodetectors by structural design.

Keywords: THz imaging; VO2(B); bolometric effect; broad-band photoresponse.