Two-color random laser based on a Nd3+ doped crystalline powder

Two-color random laser (RL) emission is demonstrated for the first time in a neodymium (Nd3+) doped nanocrystalline powder. Emissions at 1063.5 and 1065.1 nm, due to the Nd3+ transition 4F3/2 →4I11/2 in NdAl3(BO3)4 nanocrystals, were observed by exciting the powder in resonance with the Nd3+ transition 4I9/2→4F5/2, at 811 nm. The dual-wavelength emission is attributed to the radiative decay from two nonequivalent site-symmetries occupied by the Nd3+ in the NdAl3(BO3)4 crystalline structure. The behavior of the Nd3+ emissions versus the samples׳ temperature indicates the possibility of the RL application as a near infrared optical sensor with a large thermal sensitivity of 0.020 °C−1.