Spectroscopic investigation of 2.0 µm emission in Ho³⁺-doped fluoroindate glasses

Abstract

In this paper we report the optical characterization of Ho3+-doped fluoroindate glasses with the following composition (40 − x)InF3–20SrF2–16BaF2–20ZnF2–2GdF3–2NaF–xHoF3 with x = 1.0, 2.0, 2.5, 3.0, 4.0, 5.0, 6.0, 8.0 and 9.0 mol%. This investigation was done by means of absorption, fluorescence and lifetime measurements. The phenomenological intensity parameters Ωλ (λ = 2, 4, 6) were calculated using the standard Judd–Ofelt theory. In order to evaluate potential applications of the 5I7 → 5I8 Ho3+ emission at 2.0 µm, the radiative lifetime, total transition rate and emission cross section were determined. The effect of Ho3+ concentration on the fluorescence intensity and lifetimes was analysed. It was concluded that the non-radiative losses of the 5I7 level are mainly due to energy migration among Ho3+ ions followed by energy transfer to quenching impurities.

Enhanced Broadband 2.0 μm Emission and Energy Transfer Mechanism in Ho–Bi Co‐Doped Borophosphate Glass

“…However, the application of fluoride glass is limited owing to its poor thermal stability and chemical durability. Rare‐earth ions‐doped phosphate glass has attracted more interest recently for it can be used as a host in high‐power level laser system and have a fine solubility for rare‐earth ions . In our work, Al 2 O 3 , Y 2 O 3 , and B 2 O 3 were introduced into phosphate glass to modify the glass structure and to improve spectroscopic properties because the formation of a local bonding environment of oxide and Al, Y, B around Ho 3+ can improve thermal stability and chemical durability of phosphate glass.…”

Numerical Design of a Gain-Switched Pulsed Laser at 3.92 μm Wavelength Based on a Ho3+-Doped Fluoroindate Fiber

“…As an example, dysprosium and holmium ions allow emission at wavelengths beyond 3 [12,25]. Recently, holmium-doped fluoroindate fibers have been characterized [25][26][27][28][29] and CW lasers emitting at = 2.875 [30] and = 3.92 [31,32], pumped at = 1120 and = 888 respectively, have been demonstrated. For that pertaining the pulsed laser operation, emissions at the wavelength = 2.106 [33] and in the = 2.95 − 3.015 range [34] have been obtained.…”