EFFECTS OF ENERGY-TRANSFER AMONG ER-+3 IONS ON THE FLUORESCENCE DECAY AND LASING PROPERTIES OF HEAVILY DOPED ER-Y3AL5O12

Nonexponential fluorescence decay has been observed from both 4I11/2 and 4I13/2 states of Er3+ ions in heavily doped Er: YAG at room temperature. Processes of cross relaxation that originate in these states are shown to be responsible. Rate equations that include cross-relaxation processes are written and numerically solved, to result in the determination of the cross-relaxation coefficients. It is found that these coefficients do not change with Er3+ concentration. The effects of the cross-relaxation processes of Er3+ ions on fluorescence decay and lasing properties are discussed. © 1990 Optical Society of America.