Characteristic FET devices based on InSb nanowires have n-type conductivity because of the Sb vacancies. Meanwhile, InSb nanowires have an electron concentration of 3.6× 1017 cm−3 and an electron mobility of 215.25 cm2 V−1 s−1. Individual InSb nanowire was fabricated for M-IR photodetectors based on the M-S-M structure. A power-law dependence of the photocurrent on the light intensity was observed, which suggests the existence of defect states that are consistent with an n-type conductivity mechanism in the InSb nanowires. Moreover,

the photodetectors exhibit good photoconductive performance, good stability and reproducibility, superior responsivity (8.4 × 104 A W−1), and quantum LY2874455 efficiency (1.96 × 106%). These unique properties are attributed to the high surface-to-volume ratio and superior crystallinity of InSb nanowires. In addition, the M-S-M structure

can further enhance N e (or RAD001 ΔI) and the electron transport speed, significantly increasing the sensitivity of the photodetectors. The superior photoelectric properties of InSb nanowires are highly promising for application in high-sensitivity and high-speed nanoscale optical communication devices and photodetectors. Authors’ information CHK and WCC are PhD students at National Tsing Hua University. SJL holds a professor position at National Tsing Hua University. JMW holds an associate professor position at National Tsing Hua University. Acknowledgments The authors thank Mr. Guo-Kai Hsu for the helpful SEM analyses, Mr. Hsin-I Lin for the helpful FIB experiment, and the financial

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