Interference-Resisting Mechanoluminescence Ratiometric Dosimetry

Accurate and reliable radiation dosimetry is critical for applications ranging from cancer radiotherapy to nuclear safety and space exploration. While thermoluminescence and optically stimulated luminescence serve as benchmark technologies, their inherently destructive readout mechanisms preclude the straightforward, repeated verification of an absorbed dose and require complex laboratory procedures. Here, we propose a novel mechanoluminescence (ML) ratiometric dosimetry. It depends on KMgF₃:Sm^2+,3+ that can exhibit both ML at 685 nm (Sm²⁺: ⁵D₀→⁷F₀) and 602 nm (Sm³⁺: ⁴G_5/2→⁶H_7/2) under external force stimulation. The ML intensity ratio of the 602 nm band to the 685 nm band increases linearly with increasing the radiation dosage of x-rays. This ratiometric approach provides a robust internal self-calibration, making the readout immune to fluctuations in stress magnitude or duration, a fatal flaw in prior ML intensity-based methods. Therefore, we can obtain the x-ray dose simply by pressing the KMgF₃:Sm^2+,3+ samples. This strategy allows for multiple, nondestructive measurements, enabling on-demand verification of radiation doses with unparalleled simplicity.