arXiv:cond-mat/0505059 · Physical Review Letters
Microscopic Measurement of Photon Echo Formation in Groups of Individual Excitonic Transitions
W. Langbein, Brian Patton
Abstract
The third-order polarization emitted from groups of individual localized excitonic transitions after pulsed optical excitation is measured. We observe the evolution of the nonlinear response from the case of a free polarization decay for a single transition, to that of a photon echo for many transitions. The echo is shown to arise from the mutual rephasing of the emission from individual transitions.