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We study the evolution of a quantum dot controlled by a frequency-swept (chirped), linearly polarized laser pulse in the presence of carrier-phonon coupling. The final occupation of the exciton state is limited both due to phonon-induced transitions between the adiabatic spectral branches and because of phonon-assisted transitions to the biexcitostate. When the biexciton shift is large enough, the quantum dot can be modeled as a two-level system, which corresponds to excitation with circularly polarized light. For this case, we compare different methods of simulations: (i) a time convolutionless method, (ii) correlation expansion and (iii) path integrals. We show that results obtained from these methods agree perfectly at temperatur. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We study the dynamics of a semiconductor quantum dot coupled to phonons and laser light in the limit of strong electronic confinement. Using real time path integrals our numerical results are nonperturbative with respect to both, the carrier-light and the carrier-phonon coupling. As it is known the damping of Rabi rotations is a non-monotonic function of the pulse area. Here, we analyze how pulse parameters affect the resulting decay-reappearance of Rabi rotations, which arises from the resonant nature of carrier-phonon coupling. For longer pulses, the maximal reduction of the amplitude of Rabi rotations is shifted to higher pulse areas. In addition, for Gaussian pulses the reappearance rate is significantly reduced compared to rectangular profiles. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]