title: Optical absorption and luminescence of germanium oxygen-deficient centers in densified germanosilicate glass.
abstract: Spectroscopic properties of germanium oxygen-deficient centers were studied in vapor axial deposition and modified chemical-vapor deposition germanosilicate glass after hydrostatic densification by as much as 19%. Gaussian decomposition showed a broadening and a significant shift of the initial absorption bands at 5.11 and 5.42 eV. A threefold decrease of the 3.15-eV luminescence band was revealed, whereas the 4.25-eV luminescence band was only slightly sensitive to densification. This shows that these two bands belong to different luminescence centers. A drastic growth of a new metastable absorption band near 7.3 eV was observed. The pressure-induced changes disappeared as a result of thermal annealing. These changes are discussed with respect to in-fiber grating phenomena.
authors.forename: E M
authors.initials: EM
authors.lastname: Dianov
authors.forename: V M
authors.initials: VM
authors.lastname: Mashinsky
authors.forename: V B
authors.initials: VB
authors.lastname: Neustruev
authors.forename: O D
authors.initials: OD
authors.lastname: Sazhin
authors.forename: V V
authors.initials: VV
authors.lastname: Brazhkin
authors.forename: V A
authors.initials: VA
authors.lastname: Sidorov