Enhanced upconversion and temperature sensing study of Er3+–Yb3+ codoped tungsten–tellurite glass

Abstract

This article reports on the visible upconversion and temperature sensing behaviour of Er3+–Yb3+ doped/codoped TeO2–WO3 glasses prepared by a melting and quenching method. The upconversion emissions have been observed throughout the visible and infrared region upon 980nm and 808nm excitations and assigned suitably from different transitions of the Er3+ ion. The emission intensities of the most intense green band have been enhanced on the co-doping with theYb3+ ions with about 5.92 and 3.99 times upon 980 and 808nm excitations, respectively. The reason behind this improvement is explained on the basis of a power dependence study and an energy level structure. The colour tunability behaviour of the codoped glass has also been investigated upon both excitations. The temperature sensing performance of the prepared glass has been studied by using the fluorescence intensity ratio technique up to 745K. The results suggested that the present glass is a suitable candidate for making a high temperature sensor up to 690K with a sensitivity of about 28.72×10−4K−1.