A highly sensitive lifetime-based luminescent manometer and bi-functional pressure–temperature sensor based on a spectral shift of the R-line of Mn⁴⁺ in K₂Ge₄O₉

As presented in the manuscript the K₂Ge₄O₉:Mn⁴⁺ can be used as a luminescent pressure and temperature sensor. The pressure sensing can be achieved based on the kinetics of the 2E state luminescence and the spectral position of the R line can be used for temperature sensing.