Institution: | a Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka, Moscow region, Russia b Materials and Structures Laboratory, Tokyo Institute of Technology, R3-10, 4259 Nagatsuta, Yokohama 226-8503, Japan c JST-CREST, Sanban-cho bldg, 5, Sanban-cho, Chiyoda, Tokyo 102-0075, Japan |