title: Digital Doping in Magic-Sized CdSe Clusters.
abstract: Magic-sized semiconductor clusters represent an exciting class of materials located at the boundary between quantum dots and molecules. It is expected that replacing single atoms of the host crystal with individual dopants in a one-by-one fashion can lead to unique modifications of the material properties. Here, we demonstrate the dependence of the magneto-optical response of (CdSe)13 clusters on the discrete number of Mn(2+) ion dopants. Using time-of-flight mass spectrometry, we are able to distinguish undoped, monodoped, and bidoped cluster species, allowing for an extraction of the relative amount of each species for a specific average doping concentration. A giant magneto-optical response is observed up to room temperature with clear evidence that exclusively monodoped clusters are magneto-optically active, whereas the Mn(2+) ions in bidoped clusters couple antiferromagnetically and are magneto-optically passive. Mn(2+)-doped clusters therefore represent a system where magneto-optical functionality is caused by solitary dopants, which might be beneficial for future solotronic applications.
authors.affiliation: Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Münzer
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea.|School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea.
authors.forename: Jiwoong
authors.initials: J
authors.lastname: Yang
authors.affiliation: Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany.
authors.forename: Severin
authors.initials: S
authors.lastname: Lorenz
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea.|School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea.
authors.forename: Woonhyuk
authors.initials: W
authors.lastname: Baek
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea.|School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea.
authors.forename: Hogeun
authors.initials: H
authors.lastname: Chang
authors.affiliation: Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea.|School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea.
authors.forename: Taeghwan
authors.initials: T
authors.lastname: Hyeon
authors.affiliation: Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Bacher
authors.affiliation: Werkstoffe der Elektrotechnik and CENIDE, University Duisburg-Essen , Bismarckstraße 81, 47057 Duisburg, Germany.|Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul 08826, Republic of Korea.|School of Chemical and Biological Engineering and Institute of Chemical Processes, Seoul National University , Seoul 08826, Republic of Korea.
authors.forename: Rachel
authors.initials: R
authors.lastname: Fainblat
keywords: diluted magnetic semiconductor nanostructures; magic-sized cluster; magneto-optics; single-atom doping; solotronics