title: Hot Carrier Trapping Induced Negative Photoconductance in InAs Nanowires toward Novel Nonvolatile Memory.
abstract: We report a novel negative photoconductivity (NPC) mechanism in n-type indium arsenide nanowires (NWs). Photoexcitation significantly suppresses the conductivity with a gain up to 10(5). The origin of NPC is attributed to the depletion of conduction channels by light assisted hot electron trapping, supported by gate voltage threshold shift and wavelength-dependent photoconductance measurements. Scanning photocurrent microscopy excludes the possibility that NPC originates from the NW/metal contacts and reveals a competing positive photoconductivity. The conductivity recovery after illumination substantially slows down at low temperature, indicating a thermally activated detrapping mechanism. At 78 K, the spontaneous recovery of the conductance is completely quenched, resulting in a reversible memory device, which can be switched by light and gate voltage pulses. The novel NPC based optoelectronics may find exciting applications in photodetection and nonvolatile memory with low power consumption.
authors.affiliation: Department of Physics, University of California , Davis, California 95616, United States.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Physics, University of California , Davis, California 95616, United States.
authors.forename: Xingyue
authors.initials: X
authors.lastname: Peng
authors.affiliation: Department of Applied Physics, Korea University Sejong Campus , Sejong 339-700, Republic of Korea.
authors.forename: Hong-Seok
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Applied Physics, Korea University Sejong Campus , Sejong 339-700, Republic of Korea.
authors.forename: Taeho
authors.initials: T
authors.lastname: Kim
authors.affiliation: Department of Applied Physics, Korea University Sejong Campus , Sejong 339-700, Republic of Korea.
authors.forename: Sanghun
authors.initials: S
authors.lastname: Jeon
authors.affiliation: Center for Optoelectronic Materials and Devices Research, Korea Institute of Science and Technology , Seoul 136-791, Republic of Korea.
authors.forename: Hang Kyu
authors.initials: HK
authors.lastname: Kang
authors.affiliation: Center for Optoelectronic Materials and Devices Research, Korea Institute of Science and Technology , Seoul 136-791, Republic of Korea.
authors.forename: Wonjun
authors.initials: W
authors.lastname: Choi
authors.affiliation: Center for Optoelectronic Materials and Devices Research, Korea Institute of Science and Technology , Seoul 136-791, Republic of Korea.
authors.forename: Jindong
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Applied Physics, Korea University Sejong Campus , Sejong 339-700, Republic of Korea.
authors.forename: Yong-Joo
authors.initials: YJ
authors.lastname: Doh
authors.affiliation: Department of Physics, University of California , Davis, California 95616, United States.
authors.forename: Dong
authors.initials: D
authors.lastname: Yu
keywords: Nanowire; hot carriers; indium arsenide; negative photoconductance; nonvolatile memory; scanning photocurrent microscopy