[1] Univ Plymouth, Plymouth PL4 8AA, Devon, England
[2] Vienna Univ Technol, Inst Phys Expt, A-1040 Vienna, Austria
[3] Magnetfabrik Schramberg, D-78713 Schramberg, Germany
[4] VACUUMSCHMELZE GMBH, D-63450 Hanau, Germany
[5] CNRS, F-38042 Grenoble, France
[6] Mecelec Dev Ltd, Gloucester GL2 5QT, England