1. Univ. Grenoble Alpes, INAC-SP2M, L_Sim, Grenoble, France and CEA, INAC-SP2M, L_Sim, Grenoble, France
2. STMicroelectronics, 850 rue J. Monnet, 38926 Crolles, France
3. CEA, LETI-MINATEC, 38000 Grenoble, France
4. IEMN—Dept. ISEN, UMR CNRS 8520, Lille, France