Magnetic field effects on the fluorescence of Cr3+ in GdAlO3

Abstract

The fluorescence spectrum of Cr3+ in GdAlO3 has been examined at 4.2 K as a function of magnetic field up to 60 kG. The resulting splitting of the 2E 4A2 emission lines are explained in terms of a modified molecular field approximation, which incorporates the effect of the spin fluctuations. The exchange constant in the relaxed excited state is found to be 1.2 cm-1, which differs from that reported from absorption data. It is suggested that the difference may be related to the Frank-Condon effect.