1. Condensed Matter Theory Group Materials Theory Division Department of Physics and Astronomy Uppsala University Box 516 75120 Uppsala Sweden
2. Laboratoire de Physique des Matèriaux et Modélisations des Systèmes LP2MS) Faculty of Sciences Department of Physics Moulay Ismail University Meknes Morocco
3. Applied Materials Physics Department of Materials Science and Engineering Royal Institute of Technology (KTH) S-100 44 Stockholm Sweden