Open AccessValley-to-peak intensity ratio thermometry based on the red upconversion emission of Er^3+
Author(s) -
Leipeng Li,
Weiqi Xu,
Longjiang Zheng,
Feng Qin,
Yuan Zhou,
Liang Zhang,
Zhiguo Zhang,
Wenwu Cao
Publication year - 2016
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.24.013244
Subject(s) - photon upconversion , excited state , phosphor , materials science , excitation , optics , laser , laser diode , diode , emission intensity , ground state , intensity (physics) , atomic physics , stark effect , emission spectrum , physics , spectral line , optoelectronics , luminescence , quantum mechanics , astronomy
Upon 976 nm diode laser excitation, the temperature dependence of the red upconversion emission of Er 3+ in CaWO 4 :Yb 3+ /Er 3+ phosphor was studied from 298 to 478 K. The spectrum was verified to consist of two Stark components originating from two Stark sublevels of 4 F 9/2 excited state to 4 I 15/2 ground state of Er 3+ . The valley-to-peak intensity ratio (VPR) of this double-peak spectrum was found to increase linearly with the rise of temperature. The maximum relative sensitivity of this VPR method was obtained to be about 0.20% K -1 at 298 K. Moreover, a study on the power dependence was also performed, suggesting that VPR method is immune to the pump power and is thus suitable for monitoring the temperature.