Enhancement of 1.5 μm fluorescence signal from Er³⁺ due to Yb³⁺ in yttrium silicate powders pumped at 975 and 808 nm

Abstract

The effect of the presence of ytterbium (Yb 3+ ) on the near-infrared (NIR) emission profile of erbium (Er 3+ ), more specifically the 4 I 13/2 → 4 I 15/2 radiative transition around 1.5 μm, in yttrium silicate crystalline ceramic powders prepared by combustion synthesis was investigated under different NIR laser excitation wavelengths (λ=808 and 975 nm). Enhancement of fluorescence around 1.5 μm due to the presence of Yb 3+ was observed, which has potential use in medicine (NIR-III biological window) and optical communications (C-band transmission window). Two different excitation channels involving energy transfer between Er 3+ and Yb 3+ were studied: one involving the sensitization of Er 3+ by Yb 3+ (for λ=975 nm laser light excitation) and the other involving direct excitation of Er 3+ with Yb 3+ acting as an energy reservoir (for λ=808 nm laser light excitation). The energy transfer mechanisms of both processes are discussed in the text.

Broadband light emission induced by laser absorption and optimized by thermal injection in Nd3+:Y2SiO5 ceramic powder

“…The sample fully crystallizes in a combination of two Y 2 SiO 5 monoclinic phases with space groups P121/c1 (X1‐Y 2 SiO 5 ) and I12/a1 (X 2 ‐Y 2 SiO 5 ). The predominance of one phase over the other is governed by the heat‐treatment temperature and rare‐earth doping concentration . In the current work, samples were found to have predominance of phase X 1 ‐Y 2 SiO 5 (63%) over X 2 ‐Y 2 SiO 5 (37%).…”

“…The predominance of one phase over the other is governed by the heat-treatment temperature and rareearth doping concentration. 20,22,23 In the current work, samples were found to have predominance of phase X 1 -Y 2 SiO 5 (63%) over X 2 -Y 2 SiO 5 (37%). The Scherrer equation was used to estimate the average crystallite size and the value found was ~15 nm.…”

“…Yttrium silicates ceramic powders were prepared by combustion synthesis. 20,22,23 First, Nd(NO 3 ) 3 ‧6H 2 O (Aldrich, 99%), Y(NO 3 ) 3 ‧6H 2 O (Aldrich, 98%), SiO 2 (fumed, 0.014 µm, Sigma), and CH 4 N 2 O (99.5%, Sigma) were mixed in a proper molar ratio in 25 mL of deionized water and stirred for 10 minutes at room temperature when a transparent gel is formed. Then, the gel is placed in a preheated oven (500°C) and after around 10 minutes the gel decomposes, dehydrates, and undergoes combustion of the flame type.…”