title: Flexible Self-Powered GaN Ultraviolet Photoswitch with Piezo-Phototronic Effect Enhanced On/Off Ratio.
abstract: Flexible self-powered sensing is urgently needed for wearable, portable, sustainable, maintenance-free and long-term applications. Here, we developed a flexible and self-powered GaN membrane-based ultraviolet (UV) photoswitch with high on/off ratio and excellent sensitivity. Even without any power supply, the driving force of UV photogenerated carriers can be well boosted by the combination of both built-in electric field and piezoelectric polarization field. The asymmetric metal-semiconductor-metal structure has been elaborately utilized to enhance the carrier separation and transport for highly sensitive UV photoresponse. Its UV on/off ratio and detection sensitivity reach to 4.67 × 10(5) and 1.78 × 10(12) cm·Hz(0.5) W(1-), respectively. Due to its excellent mechanical flexibility, the piezoelectric polarization field in GaN membrane can be easily tuned/controlled based on piezo-phototronic effect. Under 1% strain, a stronger and broader depletion region can be obtained to further enhance UV on/off ratio up to 154%. As a result, our research can not only provide a deep understanding of local electric field effects on self-powered optoelectronic detection, but also promote the development of self-powered flexible optoelectronic devices and integrated systems.
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Mingzeng
authors.initials: M
authors.lastname: Peng
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Yudong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Aifang
authors.initials: A
authors.lastname: Yu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Caihong
authors.initials: C
authors.lastname: Liu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Liu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wu
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Xieqing
authors.initials: X
authors.lastname: Shi
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Jinzong
authors.initials: J
authors.lastname: Kou
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.
authors.forename: Junyi
authors.initials: J
authors.lastname: Zhai
authors.affiliation: Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences , Beijing 100083, China.|School of Materials Science and Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332-0245, United States.
authors.forename: Zhong Lin
authors.initials: ZL
authors.lastname: Wang
keywords: UV photoswitch; flexible optoelectronic sensing; on/off ratio; piezo-phototronic; self-powered