Anti-Stokes fluorescence cooling of nanoparticle-doped silica fibers
Abstract
The first observation of cooling by anti-Stokes pumping in nanoparticle-doped silica fibers is reported. Four Yb-doped fibers fabricated using conventional modified chemical vapor deposition (MCVD) techniques were evaluated, namely, an aluminosilicate fiber and three fibers in which the Yb ions were encapsulated in CaF2, SrF2, or BaF2 nanoparticles. The nanoparticles, which oxidize during preform processing, provide a modified chemical environment for the Yb3+ ions that is beneficial to cooling. When pumped at the near-optimum cooling wavelength of 1040 nm at atmospheric pressure, the fibers experienced a maximum measured temperature drop of 20.5 mK (aluminosilicate fiber), 26.2 mK (CaF2 fiber), and 16.7 mK (SrF2 fiber). The BaF2 fiber did not cool but warmed slightly. The three fibers that cooled had a cooling efficiency comparable to that of the best previously reported Yb-doped silica fiber that cooled. Data analysis shows that this efficiency is explained by the fibers’ high critical quenching concentration and low residual absorptive loss (linked to sub-ppm OH contamination). This study demonstrates the large untapped potential of nanoparticle doping in the current search for silicate compositions that produce optimum anti-Stokes cooling.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 13, 2022
- Source ID
- 10.1364/ol.457206
Entities
People
- Bailey Meehan
- John Ballato
- Magnus Engholm
- Martin Bernier
- Mary Ann Cahoon
- Michel J. F. Digonnet
- Peter D. Dragic
- Pierre-Baptiste Vigneron
- Thomas W. Hawkins
- Tommy Boilard
Organizations
- Air Force Office of Scientific Research
- Clemson University
- Laval University
- Mid Sweden University
- Stanford University
- University of Illinois Urbana–Champaign