Strain-dependent fluorescence spectroscopy of nanocrystals and nanoclusters in Cr:YAG crystalline-core fibers and its impact on lasing behavior
Journal
Journal of Physical Chemistry C
Journal Volume
116
Journal Issue
49
Pages
26052-26059
Date Issued
2012
Author(s)
Abstract
We report the results of our experimental investigation on the strain field distribution in Cr:Y3Al5O12 (Cr:YAG) double-clad crystal fiber (DCF) via spatially resolved near-field imaging in the visible (Cr3+) and near-infrared (Cr4+) spectral regions. The efficient and low-threshold lasing from Cr4+:YAG DCF is well-described by a minimization of the localized strain field in the core due to the thermal expansion coefficient mismatch between YAG crystalline core and polycrystalline inner cladding (mixture of γ-Al2O3 nanocrystal and Y2O3-Al2O3-SiO 2 glass). The Cr4+ fluorescence is found to be at a maximum for the DCF with a core diameter around 20 μm where the strain field in the Cr4+:YAG DCF laser is near zero. The results are presented and discussed. © 2012 American Chemical Society.
Type
journal article