[1
]ISNI 0000 0000 9119 2714, GRID grid.420187.8, Paul-Drude-Institut für Festkörperelektronik, ; Hausvogteiplatz 5-7, D-10117 Berlin, Germany
[2
]ISNI 0000 0004 1758 7362, GRID grid.472716.1, Institute for Microelectronics and Microsystems (IMM), Consiglio Nazionale delle Ricerche
(CNR), ; VIII Strada 5, I-95121 Catania, Italy
[3
]ISNI 0000 0001 2300 0941, GRID grid.6530.0, Dipartimento di Fisica, Università di Roma “Tor Vergata”, ; Via della Ricerca Scientifica 1, I-00133 Rome, Italy
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