Fluorescence Intensity Ratio‐based temperature sensor with single Nd^{3 +} :Y₂O₃ nanoparticles: Experiment and theoretical modeling

Abstract

A thermometer based on single Nd3 + :Y2O3 nanoparticles is reported. The nanothermometer relies on the ratio of thermally coupled Nd3 + emission lines accessible by either continuous‐wave upconversion under 880 nm or downconversion under 532 nm excitation wavelengths. Both processes are modeled through rate equation systems based on multiphonon interactions between excited luminescent states, which led to excellent agreement with the experimental data. Moreover, the Y2O3 effective phonon mode energy was determined, showing the appropriateness of the theoretical approach used. The system presented a relative sensitivity up to 1.36% at 300 K while working within the first biological window, thus particularly useful for biological sensing applications.

Single Er3+, Yb3+: KGd3F10 Nanoparticles for Nanothermometry

“…It gives the uncertainty of a temperature measurement as a result of the smallest area increment that can be measured by LIR. δT is given by ( Galvão et al, 2021a ): Where δ(LIR)/LIR is the relative error of temperature measurement parameter LIR , which value in our case is 0.14%. Therefore, δT ≈ 0.1 K, being typical value for NPs-based sensors ( Martín et al, 2011 ; Galvão et al, 2021b ).…”

“…The laser power pump was changed by using different combinations of neutral density filters with various optical densities. Details of the optical setup and the local temperature control system can be found in a previous work ( Galvão et al, 2021a ).…”

“…The thermometric properties of luminescence materials, including the excited state lifetime ( Jiang et al, 2021 ), emission shift ( Kolesnikov et al, 2019 ) and luminescence intensity ratio (LIR) ( Runowski et al, 2020 ; Galvão et al, 2021a ), have been extensively studied for their non-contact operating mode, fast measurement, and high precision and resolution. Compared to other optical thermometry methods, the LIR technique can avoid the influences of spectral losses and fluctuation of excitation sources, so it is highly reliable, improves measurement accuracy, and is easy to operate ( Brites et al, 2016 ).…”

Review—Structural and Optical Interpretations on Phosphor-Based Optical Thermometry

“…92 Fluorescence intensity ratio (FIR).-Generally, in rare earthdoped materials, the Fluorescence Intensity Ratio (FIR) is an effective temperature measurement method based on the change in the relative intensities of two radiative transitions. 94 It has practical benefits over alternative thermometry methods like fluorescence lifespan measurements because, among other things, it can be carried out with continuous-wave excitation and is resistant to pump light variations. The fluorescence intensity ratio has received the most attention among luminescent temperature read-out techniques because it is straightforward, the equipment is affordable, and, most significantly, it is ratiometry and self-referential.…”

Correction Due to Nonthermally Coupled Emission Bands and Its Implications on the Performance of Y2O3:Yb3+ /Er3+ Single-Particle Thermometers

“…Besides this, Ln 3+ systems are well-known also for their relatively high upconversion (UC) efficiency . However, to achieve higher spatial resolutions in thermometry experiments, the single-particle measurement level must be accomplished, and a thorough investigation of Ln 3+ systems in this regime is under current discussion in the literature. − …”