title: Effect of the surface-plasmon-exciton coupling and charge transfer process on the photoluminescence of metal-semiconductor nanostructures.
abstract: The effect of direct metal coating on the photoluminescence (PL) properties of ZnO nanorods (NRs) has been investigated in detail in this work. The direct coating of Ag nanoparticles (NPs) induces remarkable enhancement of the surface exciton (SX) emissions from the ZnO NRs. Meanwhile, the charge transfer process between ZnO and Ag also leads to notable increment of blue and violet emissions from Zn interstitial defects. A thin SiO2 blocking layer inserted between the ZnO and Ag has been demonstrated to be able to efficiently suppress the defect emission enhancement caused by the direct contact of metal-semiconductor, without weakening the surface-plasmon-exciton coupling effect. A theoretical model considering the type of contacts formed between metals, ZnO and blocking layer is proposed to interpret the change of the PL spectra.
authors.affiliation: Wuhan National Laboratory for Optoelectronics, School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Yin
authors.forename: Chuang
authors.initials: C
authors.lastname: Yue
authors.forename: Yashu
authors.initials: Y
authors.lastname: Zang
authors.forename: Ching-Hsueh
authors.initials: CH
authors.lastname: Chiu
authors.forename: Jinchai
authors.initials: J
authors.lastname: Li
authors.forename: Hao-Chung
authors.initials: HC
authors.lastname: Kuo
authors.forename: Zhihao
authors.initials: Z
authors.lastname: Wu
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Fang
authors.forename: Changqing
authors.initials: C
authors.lastname: Chen