1. Department of Materials Science and NanoEngineering, Rice University, Houston, Texas 77005, United States
2. Centre d’Elaboration de Matériaux et d’Etudes Structurales, UPR 8011, CNRS-Université de Toulouse, 29 Rue Jeanne Marvig, BP 94347, F-31055 Toulouse, France
3. Laboratoire National des Champs Magnétiques Intenses, UPR 3228, CNRS-UJF-UPS-INSA, Grenoble and Toulouse, France