Optical Thermometry Based on Vibration Sidebands in Y2MgTiO6:Mn4+ Double Perovskite

Mn4+-doped Y2MgTiO6 phosphors are synthesized by the traditional solid-state method. Powder X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectrometer are employed to characterize the samples. The Mn4+-doped Y2MgTiO6 phosphors show the far-red emission at similar to 715 nm, which is assigned to the E-2(g) -> (4)A(2) spin-forbidden transition of Mn4+. The temperature dependent luminescent dynamics of Mn4+ is described by a complete model associated with electron lattice interaction and spin orbit coupling. The noncontact optical thermometry of Y2MgTiO6:Mn4+ is discussed based on the fluorescence intensity ratio of thermally coupled anti-Stokes and Stokes sidebands of the efficient nm far-red emission in the temperature range of 10-513 K. The maximum sensor sensitivity of Y2MgTiO6:Mn4+ is determined to be as high as 0.001 42 K-1 at 153 K, which demonstrates potential applications for the optical thermometry at low-temperature environments.