LUMINESCENCE AND DYNAMICS IN TM3+NAYF4

Observation of the luminescence of Tm3+:NaYF4 when the laser light is absorbed into the (1)G(4) excited state (H-3(6) --> (1)G(4)) at 300 and 77 K is reported. Several emission bands were recorded in the blue and the red wavelength ranges. Time resolved spectroscopy and luminescence decays are used to identify unambiguously the emission originating from the (1)G(4), D-1(2) and H-3(4) states. Occurrence of emission from both D-1(2) and H-3(4) is discussed in terms of stepwise excitation and cross-relaxation processes.