Efficient optical refrigeration in Yb3+:YLiF4 at cryogenic temperatures via pulsed excitation

摘要

A theoretical cooling scheme based on pulsed excitation is presented to facilitate efficient optical refrigeration at cryogenic temperatures. The mechanism of optical refrigeration with pulsed excitation is described by a simplified cooling model founded on a density matrix. Simulated results show that for the Yb3+ :YLip4 crystal with doping concentration of 10% and background absorption of 10(-4) cm(-1), optical refrigeration via picosecond pulsed excitation is competitive at a temperature of lower than 100 K due to its high cooling efficiency and may advance the cooling temperature to the boiling point of nitrogen. (C) 2018 Optical Society of America.