Recent developments in heat management of oxide nanocomposite silica optical fibers and glass rods through laser cooling

This study presents the fabrication of ytterbium-doped lanthanum-aluminosilicate (LAS) glasses using the modified chemical vapor deposition (MCVD) technique combined with solution doping. The resulting samples exhibit nearly perfect quantum efficiencies and background absorptions below 10 dB·km⁻¹. A rod sample with a core diameter of 750 microns, with a 2000 microns cladding, was pumped using a 1070 nm laser, under ambient conditions, resulting in ASFC of -7.9 K, from room temperature.