Investigating the Potential of Cr<sup>3+</sup>-Doped Pyroxene for Highly Sensitive Optical Pressure Sensing
Maja Szymczak, Ke Su, Lefu Mei, Marcin Runowski, Przemysław Woźny, Qingfeng Guo, Libing Liao, Ł. Marciniak
Abstract
Luminescent manometry has gained significant popularity in recent years due to its capability to provide in situ pressure measurements in a remote manner. Therefore, there is a growing need to identify phosphors with pressure-dependent spectroscopic properties that can be utilized to develop highly sensitive pressure sensors operating over a wide pressure range. Hence, we present a novel temperature-invariant luminescent manometer based on Cr 3+ ion emission in pyroxene Ca 0.8 Sr 0.2 MgSi 2 O 6:Cr 3+ . We utilized two readout modes, including an innovative luminescent pressure sensing ratiometric approach based on the broad emission band associated with the 4 T 2g → 4 A 2g electronic transition of Cr 3+ ions. This approach provided an exceptionally high sensitivity of S R = 50.7 ± 0.5% GPa –1 and ensured temperature-independent pressure measurements, thus offering highly reliable readouts. Furthermore, the proposed readout mode, which leverages changes in luminescence kinetics, demonstrated high sensitivity at high pressure at around 5 GPa ( S R ∼ 8 ± 0.2% GPa –1 ) surpassing the performance of luminescence kinetics-based manometers reported to date. Consequently, Ca 0.8 Sr 0.2 MgSi 2 O 6:Cr 3+ emerges as a highly promising phosphor with significant application potential for pressure sensing across a broad pressure range.