Enhancement of the 1.31-μm emission properties of Dy³⁺-doped Ge–Ga–S glasses with the addition of alkali halides

Abstract

Alkali halides such as KBr, KI, CsBr, and CsI were added to Dy3+-doped Ge–Ga–S glasses, and their effects on the 1.31-μm emission property were investigated. The intensities of the 1.31-μm emission (6F11/2 · 6H9/2 → 6H15/2) increased at the expense of the 1.75-μm emission intensity (6H11/2 → 6H15/2) with the alkali halide addition. The lifetimes of the 1.31-μm emission level also increased as much as 35 times from 38 μs for Ge–Ga–S glass to 1320 μs for the glass containing 10 mol% CsBr. These enhancements occurred only when the ratio of MX (M = K, Cs; X = Br, I)/Ga was equal to or larger than unity. Raman spectra of Ge–Ga–S–CsBr glasses indicated the formation of [GaS3/2Br]− complexes, which provide the preferred sites for Dy3+. Due to this new local environment of Dy3+, the multiphonon relaxation rates from the Dy3+:6F11/2 · 6H9/2 level decreased by approximately four orders of magnitude. The enhancement in the 1.31-μm emission properties with alkali halide addition supports the potentials of these glasses as hosts for the Dy3+-doped fiber-optic amplifiers.

Post annealing effects on the properties of sputtered nano‐crystallite indium tin oxide thin films on flexible polyimide substrate

“…These parameters are larger than their standard values; indicating that as grown films are strained and similar results has been reported for ITO deposited on glass substrate [16]. This strain can be related to oxygen deficiency [28,29] and thermal expansion coefficient mismatch between the ITO films (7.2×10 -6 /°C) [30] and Kapton HN substrate (20×10 -6 /K) [24]. …”

Preparation and properties of GeSe2-Ga2Se3-KBr new chalcohalide glasses

“…Glass-forming region in the GeSe 2 -Ga 2 Se 3 -KBr pseudo-ternary system. Br/Ga ratio [3]. In our studied glasses, when Br/Ga ratio is smaller than 0.5, Br atoms mainly bonded to Ga in the form [8,9].…”

“…Selenium-based chalcogenide glasses have been widely studied during the past several decades due to their potential applications for infrared (IR) optics and optoelectronics [1][2][3][4][5][6]. These glasses are typically transparent from 1 to 16 m spectral region but opaque in the visible light region, which makes the quality control of IR system complicated and therefore limits their applications.…”

Upconversion luminescence properties of Er3+ doped GeS2-Ga2S3-KCl chalcohalide glasses

“…Heo et al [15] have also proved that rare earth ions acted as charge compensators for [GaS 4 ] tetrahedra in Ge-Ga-S chalcogenide glasses by Raman spectroscope analysis. With CsBr addition, edge shared [GaS 4 ] tetrahedra transforms to [GaS 3/2 Br] − units [16]. It is reasonable to propose that Er 3+ ions in 56GeS 2 -24Ga 2 S 3 -20KCl glass is surrounded by [Ga 2 S 6/2 ] units and [GaS 3/2 Cl] − units, as shown in Fig.…”