Affiliation: | (1) Department of Physics, University of Osnabr?ck, Barbarastr. 7, 49069 Osnabr?ck, Germany;(2) Faculty of Physics, Department for Experimental Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria;(3) IBM Research Division, San Jose, CA, USA;(4) IBM Almaden Research Center, 650 Harry Road, 95120 San Jose, CA, USA;(5) Optical Sciences, University of Arizona, 1630 East University Boulevard, 85721 Tucson, AZ, USA |