Absorptive and dispersive optical responses of excitons in a single quantum dot. B. Alén, A. Högele, M. Kroner, S. Seidl, K. Karrai, R. J. Warburton, A. Badolato, G. Medeiros-Ribeiro and P. M. Petroff in Appl. Phys. Lett. 89:123124 (2006).