“…The standard 4 I 11/2 -4 I 15/2 and 4 I 13/2 -4 I 15/2 bands at 980 and 1535 nm were observed for Er-doped nanoclusters, and for the case of Nd-doping, the complete set of emission bands centered at 800, 900, 1100, and 1350 nm were observed. This luminescence has been described in our recent papers [4,25]. In the case of Yb, the 2 F 5/2 -2 F 7/2 transition occurs in the PL spectrum at a wavelength of 980 nm, on the longwavelength side of the broad nanocluster luminescence band.…”