Ultraviolet and visible emissions of Er3+ in KY(WO4)2 single crystals co-doped with Yb3+ ions

In this paper we studied the luminescence of Er3+ in KY(WO4)2 co-doped with Yb3+ at room temperature and at cryogenic temperature in the 360–860 nm range. We found 13 emissions of erbium in the ultraviolet and visible range, and studied the emissions after two pump wavelengths, one at 981 nm resonant to the maximum absorption of ytterbium and one at 798 nm resonant to the 4I9/2 energy level of erbium.