title: Sensitized broadband near-infrared luminescence from bismuth-doped silicon-rich silica films.
abstract: Developing Si compatible optical sources has attracted a great deal of attention owing to the potential for forming inexpensive, monolithic Si-based integrated devices. In this Letter, we show that ultra broadband near-IR (NIR) luminescence in the optical telecommunication window of silica optical fibers was obtained for Bi-doped silicon-rich silica films prepared by a co-sputtering method. Without excess Si, i.e., Bi-doped pure silica films, no luminescence was observed in the NIR range. A broad Bi-related NIR photoluminescence appears when excess Si was doped in the Bi-doped silica. The luminescence properties depended strongly on the amount of excess Si and the annealing temperature. Photoluminescence results suggest that excess Si acts as an agent to activate Bi NIR luminescence centers and also as an energy donor to transfer excitation energy to the centers. It is believed that this peculiar structure might find some important applications in Si photonics.
authors: Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University, Rokkodai, Nada, Kobe 657-8501, Japan.
authors: Yuji
authors: Y
authors: Miwa
authors: Hong-Tao
authors: HT
authors: Sun
authors: Kenji
authors: K
authors: Imakita
authors: Minoru
authors: M
authors: Fujii
authors: Yu
authors: Y
authors: Teng
authors: Jianrong
authors: J
authors: Qiu
authors: Yoshio
authors: Y
authors: Sakka
authors: Shinji
authors: S
authors: Hayashi