Eur. Phys. J. B 16, 19-24 (2000)
https://doi.org/10.1007/s100510070244

Photoreflectance characterization of InAs/GaAs self-assembled quantum dots grown by ALMBE

¹ INFM-UdR Pavia, Via Bassi 6, 27100 Pavia, Italy
² Dipartimento di Fisica dell'Università di Parma, Viale delle Scienze 7a, 43010 Fontanini (Parma), Italy
³ INFM - Dipartimento di Fisica “A. Volta", Università di Pavia, Via Bassi 6, 27100 Pavia, Italy
⁴ CNR-MASPEC Institute, Parco delle Scienze 37a, 43010 Fontanini (Parma), Italy

Corresponding author: ^a geddo@fisav.unipv.it

Received: 17 November 1999
Published online: 15 July 2000

Abstract

We report on a photoreflectance investigation in the 0.8–1.5 eV photon energy range and at temperatures from 80 to 300 K on stacked layers of InAs/GaAs self-assembled quantum dots (QDs) grown by Atomic-Layer Molecular Beam Epitaxy. We observed clear and well-resolved structures, which we attribute to the optical response of different QD families. The dependence of the ground state transition energy on the number of stacked QD layers is investigated and discussed considering vertical coupling between dots of the same column. It is shown that Coulomb interaction can account for the observed optical response of QD families with different morphology coexisting in the same sample.