[21a-C304-1~9] 4.2 Photonics Devices, Photonic Integrated Circuit and Silicon Photonics

▲ [21a-C304-3] Optical Properties of Glass Governed by the Topological Fluctuations

〇(D)Katelyn Alyssa Kirchner^1,2, Yongjian Yang¹, Yasuhito Tanabe², Masaya Fujioka², Hiroaki Yamada³, Koji Ohara³, Shinji Kohara⁴, Junji Nishii², John C. Mauro¹, Madoka Ono^2,5 (1.Penn State Univ., 2.Hokkaido Univ. RIES, 3.JASRI, 4.NIMS, 5.AGC Inc.)

Keywords:silica glass, topological pruning, optical loss

Recent findings indicate the reduction of topological fluctuation in silica glass occurs by applying hot-compression (HC). The suppression mechanism (called topological pruning) decreases the optical loss, thereby posing great significance in the optimization of glass in optical communication fibers. The refractive index of HC silica glass increases linearly with pressure, which is reasonable considering pressure densifies the averaged structure of glass. However, the Abbe number, n, increases with pressure, indicating the dispersion of the optical oscillator strength sharpened. To determine the details of this topological fluctuation change, total structure factors are deduced from the high-energy X-ray diffraction data. Pressure induced sharpening of FSDP (First Sharp Diffraction Peak) was observed, indicating the intermediate-range ordering grows by pressure and longer-distance ordering disappeared. Using molecular dynamics reverse Monte Carlo modeling, the changes in ordering are explained as the disappearance of voids. This talk will further explain the role of topological fluctuations in the optical performance of silica glass.