LAUSR

Abstract Nd3+:Y2SiO5 crystalline ceramic powder prepared by combustion synthesis exhibited down-conversion fluorescence when the sample was exposed to CW laser radiation at 532 nm. Three emission bands centered at 879.36 nm, 804.86 nm and 753.21 nm, corresponding to transitions (4F7/2,4S3/2) → 4I9/2, (4F5/2,2H9/2) → 4I9/2 and 4F3/2 → 4I9/2, were observed. A noticeable change on the relative intensities of the transitions in the temperature range 298–673 K occured due to thermal coupling among the excited electronic states. By means of the fluorescence intensity ratio (FIR) technique, we obtained a maximum absolute sensitivity of 2.5 × 10−3 K−1 at 650 K and a relative sensitivity of 2.11% K−1 at 300 K for this material. The Judd-Ofelt standard intensity parameters ratio Ω4/Ω6, a spectroscopy quality factor for laser applications, was estimated from the FIR thermometry data and a value of 1.75 was obtained. The potential use of this material in thermal sensing at the first biological window (700–950 nm) and in lasing applications is discussed.