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Distinct types of luminescence that are activated by various stimuli in a single material offer exciting developmental opportunities for functional materials. A versatile sensing platform that exhibits photoluminescence (PL), persistent luminescence (PersL), and mechanoluminescence (ML) is introduced, which enables the sensitive detection of temperature, pressure, and force/stress. The developed Sr2MgSi2O7:Eu2+/Dy3+ material exhibits a linear relationship between ML intensity and force and can be used as an ML stress sensor. Additionally, the bandwidth of the PL emission band and the PL lifetime of this material are remarkably sensitive to temperature, with values of ≈0.05 nm K−1 and 1.29%/K, respectively. This study demonstrates PersL pressure sensing for the first time, using long‐lasting (seconds) lifetime as a manometric parameter. The developed material functions as an exceptionally sensitive triple‐mode visual pressure sensor; specifically, it exhibits: i) a sensitivity of ≈−297.4 cm GPa−1 (8.11 nm GPa−1) in bandshift mode, ii) a sensitivity of ≈272.7 cm−1/GPa (14.8 nm GPa−1) in bandwidth mode, and iii) a sensitivity of 42%GPa−1 in PL‐lifetime mode, which is the highest value reported to date. Notably, anti‐counterfeiting, night‐vision safety‐sign, 8‐bit optical‐coding, and QR‐code applications that exhibit intense PersL are demonstrated by 3D‐printing the studied material in combination with a polymer. [ABSTRACT FROM AUTHOR]

Abstract We present an optical pressure sensor KMgF 3 :Eu2+ suitable for experiments in diamond anvil cell (DAC), which we have calibrated against the ruby reference sensor at pressures ranging from atmospheric up to 30 GPa (300 kbar), at room temperature. The emission spectra of KMgF 3 :Eu2+ consist of one prominent emission line related to the 6P 7/2 → 8S 7/2 electronic transition (zero phonon line) accompanied by weak phonon sidebands. The energy of emission at atmospheric pressure was determined to be 27846 ± 7 cm−1. The edge of the excitation spectrum lies at wavelength around 325 nm (30800 cm−1) making it suitable to excite with He-Cd laser (325 nm). The sensor exhibits linear pressure shift of rate equal to −0.815 ± 0.007 cm−1/kbar at pressures up to 300 kbar. The pressure shift of the emission is totally reversible and the pressure sensor is suitable for multi cycle pressure experiments. The sensor's exceptional feature is that excitation and emission spectra lie in near UV, which makes it very convenient to use in high pressure optical measurements in visible and IR region with no interference from the sensor's luminescence. Highlights • New optical pressure sensor for high pressure experiments – KMgF 3 :Eu2+. • Sensor has been callibrated for pressures up to 300 kbar (30 GPa). • Pressure sensor is applicable at cryogenic temperatures as well as above room temperature. • Luminescence in UV range prevents interference of the sensor during high pressure optical measurements in VIS-IR range. [ABSTRACT FROM AUTHOR]