Superlattices and Microstructures 33 (2003) 63–71 www.elsevier.com/locate/jnlabr/yspmi Theory of positron superlattices and the investigation of the possibility of probing heterostructures with positrons Nadir Sekkal a,b,c,∗ , Hafid Aourag b a D´ epartement de Sciences Exactes, Ecole Normale Sup` erieure de l’Enseignement Technique, BP 1523, El M’Naouer, 31000 Oran, Algeria b Computational Materials Science Laboratory, D´ epartement de Physique, Institut de Sciences Exactes, Universit´ e de Sidi Bel Abb` es, 22000 Sidi Bel Abb` es, Algeria c Physia-Laboratory, BP 47 (RP), 22000 Sidi Bel Abb` es, Algeria Received 12 June 2002; received in revised form 2 June 2003; accepted 5 June 2003 Abstract Is it possible to confine positrons in some region of the so-called semiconducting superlattice, in the absence of any vacancies or defects, as is done with electrons? In other words, can positrons be useful for probing such structures? In this paper, our aim is to answer these questions. To that end, we calculate the bandstructures and the charge densities of positrons in these systems. Two possible superlattice configurations are considered. Interesting and new results are obtained. In the light of the present work, it is shown that the positron confinement is possible, and its utilization as a direct probing tool for superlattices is proposed. © 2003 Elsevier Ltd. All rights reserved. Keywords: Theory; Positron; Electron; Bandstructure; Confinement; GaAs–AlAs; GaAs–Ge; GaAs; AlAs; Ge; Angular correlation of annihilation radiation; ACAR 1. Introduction Positron applications in condensed matter are numerous [1]. They are used to study Fermi surfaces, defects, and to probe several other electronic properties. Some works have increased the usefulness of the positron as a probing tool in many other interesting fields of physics and technology: the positron microscope [2], the positron camera [3], the cooling of antiprotons [4], to name only a few examples. The conventional technique of the two-dimensional angular correlation annihilation radiation (2D-ACAR) has led to many interesting results for semiconductors. For example, ∗ Corresponding author. Fax: +213-43-27-44-47. E-mail address: nsekkal@yahoo.fr (N. Sekkal). 0749-6036/03/$ - see front matter © 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0749-6036(03)00045-4