Affiliation: | aMikroelektronik Centret, The Technical University of Denmark, Lyngby, DK-2800, Denmark;bInstitute of Solid State Physics, Russian Academy of Sciences, Chenogolovka, 142432, Moscow district, Russia;cTechnische Physik, Universität Würzburg, Am Hubland, Würzburg, D-97074, Germany |