"Discrete breathers and the anomalous decay of luminescence"
May 19, 2011 - 7:00am
Some years ago an anomaly was noted in the decay of luminescence in certain doped alkali halides. The anomaly was eventually explained using a factor of a billion slowdown in lattice relaxation, a remarkable stretching of time scales. This slowdown was found to be caused by the creation of a ‘breather’ in the neighborhood of the dopant. Discrete breathers are nondispersive classical excitations that are known to be significant in many natural systems. In the talk I focus on the occurrence of breathers in doped alkali halides. Several more general properties of breathers have arisen from this study, among them is the quantum breather, a topic less fully explored than the classical theory because it does not yield easily to numerical simulation.