Picosecond excite-and-probe absorption measurement of the intra-2 E g E 3/2-state vibrational relaxation time in Ti3+:Al2O3

The kinetics of vibrational transitions in the 2EgE3/2 electronic state of Ti3+:Al2O3 is studied by exciting higher lying vibrational levels of the state by a 527-nm picosecond pump pulse, and monitoring the subsequent growth of population in the zero vibrational level and lower lying vibrational levels by a 3.9-μm picosecond probe pulse. An upper limit of 3.5 ps for intra-2EgE3/2 -state vibrational relaxation time is estimated.