J. Phys. I France
Volume 7, Numéro 10, October 1997
Page(s) 1221 - 1231
J. Phys. I France 7 (1997) 1221-1231
DOI: 10.1051/jp1:1997119

Excitons in V-Shaped and T-Shaped Semiconductor Quantum Well Wires

Dirk Brinkmann, Axel Löffler and Guy Fishman

Laboratoire de Spectrométrie Physique CNRS UMR 5588, Université Joseph Fourier, Grenoble 1, BP 87, 38402 Saint Martin d'Hères Cedex, France

(Received 17 February 1997, revised 28 May 1997, accepted 23 June 1997)

We give a general framework for describing electronic states in isolated quantum wires. It provides a description of both the conduction band and the valence band, taking full account of the complexity of the $\Gamma_8$ valence band. This is applied to T-shaped wires and V-shaped wires. To make a useful comparison with experimental results we calculate the exciton Rydberg. We show that in the case of the T-shaped wires hole confinement is due to the interaction with the confined electron and not due to the confining potential: the red shift of the wire exciton line with respect to that of the quantum well is mainly due to the decrease of the electron confinement energy and only partially to the increase of the exciton Rydberg. The experimental results are reproduced with non adjustable parameters.

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