title: Photocurrent response of carbon nanotube-metal heterojunctions in the terahertz range.
abstract: We investigate the optoelectronic properties of a carbon nanotube (CNT)-metal heterostructure in the terahertz range. On the basis of terahertz time-domain spectroscopy characterization of a double-walled CNT (DWNT) film, we present and analyze the photocurrent measurement for a DWNT-nickel heterojunction illuminated by continuous-wave terahertz radiation. A significant current across the junction directly induced by terahertz excitation is observed and a negative photoconductivity behavior is found to occur in the device. The photocurrent shows a linear response to the bias voltage and the illumination power within the examined range. These phenomena support the feasibility of using CNT-metal heterojunctions as novel terahertz detectors.
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Wang
authors.forename: Guowei
authors.initials: G
authors.lastname: Zhang
authors.forename: Lingbo
authors.initials: L
authors.lastname: Qiao
authors.forename: Jinquan
authors.initials: J
authors.lastname: Wei
authors.forename: Jia-Lin
authors.initials: JL
authors.lastname: Zhu
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Chen
authors.forename: Ziran
authors.initials: Z
authors.lastname: Zhao
authors.forename: Jia-Lin
authors.initials: JL
authors.lastname: Sun