DYNAMICAL PROCESSES OF THE 2.818-EV CENTER IN DIAMOND

In natural Si-rich brown diamonds a luminescence centre with a zero-ph onon line at 2.818 eV and a room temperature decay time of 1.7 ms is o ften found. The vibronic coupling and the decay characteristics of the band are analysed. The luminescence originates mainly in two sublevel s of a triplet electronic state that decays to a singlet ground state. The third triplet sublevel reaches thermal equilibrium with the other two above 40 K. The possibility of stimulated tunable emission from t his centre is discussed.