
Upconverted 5d–4f luminescence from Er3+ and Nd3+ ions doped into fluoride hosts excited by ArF and KrF excimer lasers
Keywords: 78.55.Hx; 33.80.Rv; 33.20.Ni; 42.72.Bj5d–4f Luminescence; Trivalent rare earth ions; Upconverted VUV luminescence