title: Low phonon energies and wideband optical windows of La2O3-Ga2O3glasses prepared using an aerodynamic levitation technique.
abstract: xLa2O3-(100 - x)Ga2O3binary glasses were synthesized by an aerodynamic levitation technique. The glass-forming region was found to be 20 ≤ x ≤ 57. The refractive indices were greater than 1.92 and increased linearly with increasing x. The polarizabilities of oxide ions were estimated to be 2.16-2.41 Å3, indicating that the glasses were highly ionic. The glasses were transparent over a very wide range from the ultraviolet to the mid-infrared region. The widest transparent window among the oxide glasses was from 270 nm to 10 μm at x = 55. From the Raman scattering spectra, a decrease in bridging oxide ions and an increase in non-bridging oxide ions were confirmed to occur with increasing La2O3content. The maximum phonon energy was found to be approximately 650 cm-1, being one of the lowest among oxide glasses. These results show that La2O3-Ga2O3binary glasses should be promising host materials for optical applications such as lenses, windows, and filters over a very wide wavelength range.
authors.affiliation: Materials &Advanced Research Laboratory, Nikon Corporation, 2-15-3 Konan, Minato-ku, Tokyo 108-6290, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Yoshimoto
authors.affiliation: Graduate School of Science and Technology, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.|Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
authors.forename: Atsunobu
authors.initials: A
authors.lastname: Masuno
authors.affiliation: Materials &Advanced Research Laboratory, Nikon Corporation, 2-15-3 Konan, Minato-ku, Tokyo 108-6290, Japan.
authors.forename: Motoi
authors.initials: M
authors.lastname: Ueda
authors.affiliation: Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inoue
authors.affiliation: Materials &Advanced Research Laboratory, Nikon Corporation, 2-15-3 Konan, Minato-ku, Tokyo 108-6290, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.affiliation: Materials &Advanced Research Laboratory, Nikon Corporation, 2-15-3 Konan, Minato-ku, Tokyo 108-6290, Japan.
authors.forename: Tastunori
authors.initials: T
authors.lastname: Kawashima