Roselló-Mechó Xavier, Delgado-Pinar Martina, Barmenkov Yuri O, Kir'yanov Alexander V, Andrés Miguel V
Department of Applied Physics and Electromagnetism-ICMUV, University of Valencia, C/Dr. Moliner 50, 46100 Burjassot, Spain.
Photonics Department, Centro de Investigaciones en Óptica, Loma del Bosque 115, León 37150, Mexico.
Sensors (Basel). 2021 Mar 17;21(6):2094. doi: 10.3390/s21062094.
Optical fiber characterization using whispering gallery mode resonances of the fiber itself has been demonstrated to be a powerful technique. In this work, we exploit the thermal sensitivity of whispering gallery mode resonances to characterize the pump-induced temperature increment in holmium doped and holmium-ytterbium codoped optical fibers. The technique relies on the measurement of the resonances' wavelength shift due to temperature variation as a function of the pump power. Holmium doped fibers were pumped to the second excited level 5I6 of the Ho3+ ion using a laser diode at 1125 nm and ytterbium-holmium codoped fibers to the 2F5/2 level of the Yb3+ ion by a laser diode at 975 nm. Our results demonstrate that pumping ytterbium-holmium codoped fibers at 975 nm results in dramatic thermal effects, producing a temperature increment two orders higher than that observed in holmium doped fibers pumped with a 1125 nm laser diode.
利用光纤自身的回音壁模式共振对光纤进行表征已被证明是一种强大的技术。在这项工作中，我们利用回音壁模式共振的热敏感性来表征掺钬光纤和掺钬-镱共掺光纤中泵浦诱导的温度增量。该技术依赖于测量由于温度变化导致的共振波长偏移作为泵浦功率的函数。掺钬光纤使用1125 nm的激光二极管泵浦到Ho3+离子的第二激发态5I6，而镱-钬共掺光纤则通过975 nm的激光二极管泵浦到Yb3+离子的2F5/⒉ 能级。我们的结果表明，在975 nm泵浦镱-钬共掺光纤会产生显著的热效应，导致温度增量比用1125 nm激光二极管泵浦的掺钬光纤中观察到的温度增量高两个数量级。
