Fluorescence reabsorption calculation and influence on solid-state optical cooling.
The calculation model of fluorescence reabsorption and reemission with consideration of reflection on the boundary and material size using Monte Carlo method is proposed. To validate this stochastic model, experiments were conducted, and the calculated steady state spectra showed a good agreement with measurements. Using the absorption and fluorescence spectra of Yb-doped phosphate glass by careful measurements and corrections, we calculated the redshift in the observed fluorescence spectra and external quantum efficiency caused by fluorescence reabsorption and re-emission for the samples with the geometries of cylinder and cuboid. The calculation results show that the fluorescence reabsorption and re-emission have significant influence on the cooling efficiency. The calculation results also show that the cylinder with small waist beam incident (the incident light beam diameter is much less than the size of the sample, and goes through the center of the sample) is suitable for optical cooling.
Wang
Xiaofeng
X
College of Opto-Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. wangxiaofeng@nudt.edu.cn
Chang
Shengli
S
Yang
Jiankun
J
Zhou
Mu
M
Cao
Dingxiang
D
Tan
Jichun
J