Coherent excitonic resonances of natural quantum dots studied with optical 2D Fourier transform spectroscopy

ORAL

Abstract

Optical 2D Fourier transform spectroscopy [1] is used to study the coherent nonlinear response from interfacial (or ``natural'') GaAs quantum dots [2], found within the monolayer fluctuations of a quantum well. The low temperature ($\sim $6K) spectra show excitonic resonances from both the quantum dots and the quantum well, the former having a larger inhomogeneous distribution and narrower homogeneous linewidth. Variation of the population time delay (of the excitation sequence) and lattice temperature reveals a coupling associated with the phonon mediated, incoherent relaxation from the quantum well states to the lower energy quantum dots. [1] S. T. Cundiff, T. Zhang, A. D. Bristow, D. Karaiskaj, X. Dai, Acc. Chem. Res. \textbf{42}, 1423 (2009). [2] D. Gammon, E.S. Snow, B.V. Shanabrook, D.S. Katzer, and D. Park, PRL \textbf{76}, 3005 (1996).

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Authors

  • Galan Moody

    JILA, National Institute of Standards and Technology, and University of Colorado

  • Alan Bristow

    JILA, National Institute of Standards and Technology, and University of Colorado

  • Mark Siemens

    JILA, University of Colorado at Boulder, JILA, National Institute of Standards and Technology, and University of Colorado, Deparment of Physics and JILA, University of Colorado at Boulder

  • Xingcan Dai

    JILA, National Institute of Standards and Technology, and University of Colorado

  • Denis Karaiskaj

    JILA, National Institute of Standards and Technology, University of Colorado, and University of South Florida

  • Steven Cundiff

    JILA, University of Colorado, JILA, National Institute of Standards and Technology, and University of Colorado, Boulder, JILA, National Institute of Standards and Technology, and University of Colorado, JILA, University of Colorado and NIST