1. Institute of Solid State Physics RAS, 142432 Chernogolovka, Moscow District, Russia
2. TU Dresden, Electrical and Computer Engineering, Institute of Semiconductors and Microsystems, Nöthnitzer Str. 64, 01187 Dresden, Germany
3. NaMLab gGmbH, Nöthnitzer Str. 64 a, 01187 Dresden, Germany