| Affiliation: | (1) Department of Physics, University of Illinois at Chicago Circle, 60680 Chicago, IL, USA;(2) Bell Laboratories, 07733 Holmdel, NJ, USA;(3) Bell Laboratories, 07974 Murray Hill, NJ, USA;(4) Department of Physics, USC, 90007 Los Angeles, CA, USA;(5) Gesamthochschule, Fachbereich Physik, Universität Essen, D-4300 Essen 1, Fed. Rep. Germany;(6) Stanford University, 94305 Stanford, CA, USA;(7) Fakultät für Physik, Universität Bielefeld, D-4800 Bielefeld, Fed. Rep. Germany;(8) Center for Quantum Electronics, The University of Texas at Dallas, 75080 Richardson, TX, USA;(9) Central Institute of Physics, Bucharest/Magurele, Romania;(10) Naval Research Laboratory, 20375 Washington, DC, USA;(11) IBM Research Division, 95193 San Jose, CA, USA;(12) IBM Research Laboratory, 95193 San Jose, CA, USA;(13) IBM T. J. Watson Research Center, 10598 Yorktown Heights, NY, USA |
