Abstract
The two-photon absorption and fluorescence of bulk cadmium sulfide were studied using 50-fs, 800-nm pulses from an unamplified Ti:sapphire laser. The fluorescence spectrum was measured to have a main peak at 522 nm, and the power of the fluorescence was shown to vary quadratically with the 800-nm beam power. This supports the theory that the fluorescence is excited by two-photon absorption and confirms previous work done with longer duration, higher energy excitation pulses. Pump-probe measurements provided additional confirmation of the two-photon absorption. Measured spectral broadening of the wings of the laser spectrum also was observed, which likely is due to self-phase modulation in the cadmium sulfide.
Funder
College of Saint Benedict
Saint John’s University Physics Department and the Office of Undergraduate Research and Scholars