1 Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, USA.
2 Department of Physics and Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universitat Munchen, Theresienstrasse 37, 80333 Munchen, Germany.
3 Department of Physics, Florida State University, Tallahassee, Florida 32306, USA.
4 National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA.