Coherent excitation of the quasilongitudinal and quasitransverse acoustic phonon mode in strain engineered InAs/GaAs quantum dot (QD) clusters grown on (311)B GaAs is monitored by means of time-resolved differential reflection spectroscopy. Carrier capture within the ordered QD clusters initiate coherent acoustic phonon excitation, which induces a transient modulation of the local strain-induced piezoelectric field within the QD clusters. The excited acoustic phonons then modulate the optical properties of the QDs through the quantum-confined Stark effect, causing distinct oscillations of the differential reflection signal.
Bogaart, E. W., Lippen, van, T., Haverkort, J. E. M., Nötzel, R., & Wolter, J. H. (2006). Coherent acoustic phonons in strain engineered InAs/GaAs quantum dot clusters. Applied Physics Letters, 88(14), 143120-1/3. . https://doi.org/10.1063/1.2193460