Excitons in Quantum Confined systems

Quantum confinement in semiconductor heterostructures significantly modifies the properties of excitons. Most interestingly, the impact of confinement depends crucially on the dimensionality of the confined structure. We study the features of excitons confined in 2D quantum wells, 1D quantum wires and 0D quantum dots, including the effect of disorder, Coulomb interaction and charge carrier dynamics.


Quantum well (QW) excitons

  • Effect of substrate misorientation
  • Segregated vertical QWs

 

Quantum wire (QWR) excitons

  • 2D quantum confinement effects
  • Charged 1D excitons
  • High density effects

 

Quantum dot (QD) excitons

  • Localization in disordered QWRs
  • Charged 0D excitons
  • Polarization effects

Selected publications:
 

  • F. Vouilloz, D. Oberli, M.A. Dupertuis, A. Gustafsson, F. Reinhardt and E. Kapon,
    “Polarization Anisotropy and Valence Band Mixing in Semiconductor Quantum Wires”
    Phys. Rev. Lett. 78, 1580-1583 (1997).
  • R. Ambigapathy, I. Bar-Joseph, D.Y. Oberli, S. Haacke, M.J. Brasil, F. Reinhardt, E. Kapon and B. Deveaud,
    “Coulomb Correlation and Bandgap Renormalization at High Carrier Densities in Quantum Wires”
    Phys. Rev. Lett. 78, 3579-3582 (1997).
  • E. Martinet, A. Gustafsson, G. Biasiol, F. Reinhardt, E. Kapon and K. Leifer,
    “Carrier Quantum Confinement in Self-Ordered AlGaAs V-Groove Quantum Wells”
    Phys. Rev. B 56, R7096-R7099 (1997).
  • A. Hartmann, Y. Ducommun, E. Kapon, U. Hohenester and E. Molinari,
    “Many-Body Effects in Semiconductor Quantum Dots: Observation of Multi-Charged-Excitons”
    Phys. Rev. Lett. 84, 5648 (2000).
  • A. Rudra, E. Pelucchi, D.Y. Oberli, N. Moret, B. Dwir and E. Kapon,
    “Properties of GaAs/AlGaAs Quantum Wells Grown by OMVPE using Vicinal GaAs Substrates”
    J. Crystal Growth 272, 615-620 (2004).
  • T. Otterburg, D. Y. Oberli, M.-A. Dupertuis, N.Moret, E. Pelucchi, B. Dwir, E. Kapon,
    “Enhancement of the Binding Energy of Charged Excitons in Disordered Quantum Wires”
    Phys. Rev. B 71, No. 033301 (2005).
  • M. Merano, S. Sonderegger, A. Crottini, S. Collin, P. Renucci, E. Pelucchi, A. Malko, M.H. Baier, E. Kapon, B. Deveaud and J.D. Ganiere,
    “Probing Carrier Dynamics in Nanostructures by Picosecond Cathodoluminescence”
    Nature 438, 479-482 (2005).
  • Q. Zhu, E. Pelucchi, S. Dalessi, K. Leifer, M.A. Dupertuis and E, Kapon,
    “Alloy Segregation, Quantum Confinement and Carrier Capture in Self-Ordered Pyramidal Quantum Wires”
    Nano Lett. 6, 1036-1041 (2006)