Effect of carrier transfer on the PL intensity in self-assembled In (Ga) As/GaAs quantum rings

¹ Unité de Recherche des Physiques des Semiconducteurs et Capteurs, Institut Préparatoire aux Études Scientifiques et Techniques, La Marsa 2070, Tunis, Tunisia
² Instituto de Ciencia de los Materials, Universidad de Valencia, PO Box 22085, 46071 Valencia, Spain
³ Instituto de Microelectrónica de Madrid, Isaac Newton 8, 28760 Tres Cantos, Madrid, Spain

Corresponding author: ouerghuiwalid@yahoo.fr

Received: 9 May 2006
Accepted: 9 June 2006
Published online: 23 August 2006

Abstract

We present results concerning the carrier transfer between In(Ga)As quantum rings in a stacked multilayer structure, which is characterised by a bimodal size distribution. This transfer of carriers explains the observed temperature behaviour of diode lasers based on that kind of stacked layer structures. The inter-ring carrier transfer can be possible by phonon assisted tunnelling from the ground state of the small-ring family towards the big-ring family of the bimodal size distribution. This process is thermally activated in the range 40–80 K.