Spectral and temporal properties of 5-phenyl-2-[4-(5-phenyl-1,3-oxazol-2-yl)phenyl]-1,3-oxazole (POPOP) multiphoton-excited luminescence

The results of a study of multiphoton-excited luminescence and Stimulated Raman scattering (SRS) of POPOP in a form of crystalline powder and toluene solution are presented. Two-photon and three-photon-excited luminescence in POPOP crystalline powder and toluene solution was registered under excitation by pico- and nanosecond laser pulses. Samples cooling to the temperature of liquid nitrogen leads to the appearance of an additional line in the luminescence spectrum at a wavelength of 447 nm, SRS lines intensity increasing accompanying two-photon luminescence process and changing temporal dynamics, a decrease in the contribution of the fast component in the decay time curve. •The effect of multiphoton absorption on the POPOP luminescence properties.•More efficient multiphoton luminescence for inhomogeneous form.•An additional line in luminescence spectrum of crystalline POPOP at low temperature.•The fast time component decreasing at low temperature.•The threshold nature of the SRS energy dependence accompanying TPL.