Dual-mode optical thermometry based on transparent NaY2F7:Er3+,Yb3+ glass-ceramics

NaY2F7:Er3+,Yb3+ glass-ceramics (GC) with high transmittance were well manufactured using a melt-quenching technique and subsequent thermal treatment. Structure, morphology and photoluminescence properties of all samples were thoroughly studied via X-ray diffraction, transmission and up-conversion emission spectrum. Due to the improved crystallinity after thermal treatment, the up-conversion emission intensity of GC was significantly higher than the precursor glass. The optical thermometry performances of Er3+ ions at thermally coupled (H-2(11/2)/S-4(3/2)), and non-thermally coupled energy levels (H-2(11/2)/F-4(9/2)) were explored. Their relative sensitivities (S-R) are 1.00% K-1 and 0.76% K-1 at 323 K, respectively. Moreover, their maximum temperature measurement errors (Delta T) are 0.09 K and 0.12 K at 563 K, with repeatability (R) exceeding 99% and 98%, respectively. All of the findings suggest that NaY2F7 GC are excellent self-calibration temperature measuring materials, with superior temperature resolution and repeatability.

Automated summary

NaY2F7:Er3+,Yb3+ glass-ceramics with high transmittance were successfully prepared using a melt-quenching technique and subsequent thermal treatment. The improved crystallinity led to significantly higher up-conversion emission intensity compared to the precursor glass. The Er3+ ions showed excellent optical thermometry performance with high sensitivity and temperature resolution for self-calibration temperature measurement.