Megahertz non-contact luminescence decay time cryothermometry by means of ultrafast PbI2 scintillator

Abstract

Realtime in situ temperature monitoring in difficult experimental conditions or inaccessible environments is critical for many applications. Non-contact luminescence decay time thermometry is often the method of choice for such applications due to a favorable combination of sensitivity, accuracy and robustness. In this work, we demonstrate the feasibility of an ultrafast PbI 2 scintillator for temperature determination, using the time structure of X-ray radiation, produced by a synchrotron. The decay kinetics of the scintillations was measured over the 8–107 K temperature range using monochromatic pulsed X-ray excitation. It is found that lead iodide exhibits a very fast and intense scintillation response due to excitons and donor-acceptor pairs, with the fast decay component varying between 0.08 and 0.5 ns – a feature that can be readily exploited for temperature monitoring. The observed temperature dependence of the decay time is discussed in terms of two possible mechanisms of thermal quenching – transition over activation barrier and phonon-assisted escape. It is concluded that the latter provides a better fit to the experimental results and is consistent with the model of luminescence processes in PbI 2 . We evaluated the sensitivity and estimated the accuracy of the temperature determination as ca. ±6 K at 107 K, improving to ±1.4 K at 8 K. The results of this study prove the feasibility of temperature monitoring, using ultrafast scintillation of PbI 2 excited by X-ray pulses from a synchrotron, thus enabling non-contact in-situ cryothermometry with megahertz sampling rate.

Room Temperature, Twist Angle Independent, Momentum Direct Interlayer Excitons in van der Waals Heterostructures with Wide Spectral Tunability

“…The longer lifetime can be ascribed to superposition of different recombination mechanisms including trapping of the IX in the PbI 2 defect states. , PL decay profiles of the intralayer excitons in PbI 2 and 2L-WS 2 are fitted with biexponential and single-exponential functions, respectively (Figure S5). The corresponding lifetimes are τ 1‑PbI 2 = 800 ± 1 ps, τ 2‑PbI 2 = 3.0 ± 0.1 ns, and τ WS 2 = 286 ± 1 ps, which are similar to the values obtained in the literature. , Importantly, the lifetime of the 1.58 eV peak is considerably longer than that of intralayer excitons, which further supports that the observed peak is of interlayer nature.…”

Al2O3 co-doped with Cr3+ and Mn4+, a dual-emitter probe for multimodal non-contact luminescence thermometry

“…This parameter calculated by converting the uncertainty of the parameter that is measured, δQ, by dividing it by the responsivity of the sensor, |dQ/dT|. 18,63,64 δT ¼ δQ dQ dT…”

Ultra-fast low temperature scintillation and X-ray luminescence of CsPbCl3 crystals

“…20 The scintillation light yield of CsPbX 3 single crystals is less than 1000 ph per MeV at room temperatures, 21,22 but drastically increases with cooling below 100 K. 23 This temperature range is important for specialised particle physics experiment where the use of cryogenic detectors for ionising radiation facilitates an appreciable enhancement of sensitivity. 24,25 Furthermore, the feasibility of employing fast cryogenic scintillators in nuclear imaging 26 and non-contact thermometry 27 is actively investigated. Thus, taking into account the excellent light yield and very fast decay time observed in halide perovskites at low temperature, 8,23,28 we envisage opportunities for this family of materials in scintillatorbased applications at cryogenic temperatures.…”