Dose dependent x-ray luminescence in MgF₂: Eu²⁺, Mn²⁺ phosphors

In Mg F2: Mn²⁺, Eu2+ phosphors, the x-ray excited luminescence from Eu2+ is decreased while the emission from Mn²⁺ is increased in intensity with the increase of x-ray dose. In Mg F2: Mn²⁺, the luminescence is also increased, and in MgF₂: Eu²⁺, the emission of Eu2+ is also decreased in intensity with the increase of x-ray dose. However, the intensity changes with x-ray dose in the singly doped Mg F2: Mn²⁺ and MgF₂: Eu²⁺ phosphors are much less than those in the doubly doped Mg F2: Mn²⁺, Eu2+ phosphors. The increase of Mn²⁺ emission in intensity is likely due to the breakdown of the forbidden transition by the defects created by x-ray irradiation. No conversion of Eu2+ ions to Eu3+ ions was observed in MgF₂: Eu ²⁺ phosphors during x-ray irradiation. The decrease of Eu2+ emission in intensity in Mg F2: Mn²⁺, Eu2+ must be closely related to the interaction and the energy transfer to Mn²⁺ ions. The phenomenon observed is potentially interesting for the practical applications for radiation detection, as utilizing the ratio of the two emissions from Mn²⁺ and Eu2+ for radiation detection is more sensitive and more reliable than using emission intensity change only.