Journal Article , School of Physical and Chemical Sciences–Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New ZealandInstitut für Theoretische Physik, Universität Heidelberg, Philosophenweg 12, D-69120 Heidelberg, Germany Search for other works by this author on: , School of Physical and Chemical Sciences–Te Kura Matū, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand Search for other works by this author on: , School of Physical and Chemica...