Open AccessEvaluation of thermo-optic characteristics of cryogenically cooled Yb:YAG ceramics
Author(s) -
Ryo Yasuhara,
Hiroaki Furuse,
A. Iwamoto,
Junji Kawanaka,
Takahiko Yanagitani
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.029531
Subject(s) - materials science , thermal expansion , refractive index , ceramic , optics , thermal conductivity , laser , optoelectronics , composite material , physics
The temperature dependence of the thermo-optic effect in cryogenically cooled Yb:YAG ceramics was evaluated by measuring the thermo-optic coefficient (the derivative of refractive index with respect to temperature, i.e., dn/dT), thermal expansion coefficient (α), and thermal conductivity (κ) between 70 and 300 K. These parameters significantly improved at low temperature. Observed values indicated that a laser gain medium cooled to 70 K can sustain a thermal load up to 20 times higher than that at 300 K, for comparable thermo-optic effects. To our best knowledge, this is the first quantitative evaluation of the improvement in thermo-optic characteristics of cryogenically cooled Yb:YAG ceramics.