Novel Magnetism in II-Mn-VI Type-II Quantum Dots controlled by optical excitation

****Technical Abstract**** The research in this project will develop improved understanding of novel magnetism created by optical excitation in type-II (II-Mn)-VI quantum dots, and will explore controlling magnetic properties by optical beams. Recently discovered optical and magnetic phenomena in these type-II quantum dots, as well as interesting re-entrant magnetic states predicted by theory collaborators will be investigated. The research program involves MBE growth, structural, compositional and magnetic characterization, CW and time-resolved interband magneto-optical spectroscopy and terahertz intraband spectroscopy of ensembles and single quantum dot columns, as well as associated theory. This effort will lead to a better understanding of the basic physics and materials issues of these type-II columnar quantum dots in the (II,Mn)-VI materials systems. The PIs at UB will host an Interdisciplinary Science and Engineering Partnership (ISEP) supported teacher in interdisciplinary research in their laboratories with the objective of expanding opportunities to link materials and solid state physics research to the middle and high school classroom. In addition, building on previous success, a one-week summer workshop in the second summer of the grant to provide an introduction to magnetic phenomena and their application to everyday devices will be conducted; high school teachers from the area will participate. ****Non-Technical Abstract**** This project will explore controlling magnetic properties of nanostructures using optical beams. The research team involves two senior co-PIs and theory collaborators from the University at Buffalo, a co-PI at the University of Oklahoma and collaborators in MBE growth at the National Chiao Tung University, Taiwan. The PIs will explore novel magnetic states in quantum dots that incorporate magnetic ions such as manganese. These magnetic quantum dots will serve as platform for inducing, manipulating and controlling magnetism by light. The effort will lead to a better understanding of the basic physics and materials issues of these quantum dot systems. The experiments, which will ultimately focus on individual columns of dots, are challenging, and there is a great deal of interesting physics predicted to occur in these systems, as well as likely unanticipated discoveries. The PIs at UB will host an Interdisciplinary Science and Engineering Partnership (ISEP)-supported teacher in interdisciplinary research in their laboratories with the objective of expanding opportunities to link materials and solid state physics research to the middle and high school classroom. In addition, building on previous success, a one-week summer workshop in the second summer of the grant to provide an introduction to magnetic phenomena and their application to everyday devices will be conducted; high school teachers from the area will participate.