Magnetic exchange coupling of Co/Ir multilayers B. M. AlQassem, B. A. Hamad, J. M. Khalifeh and C. Demangeat Eur. Phys. J. B, 62 4 (2008) 433-438 Published online: 22 May 2008 DOI: 10.1140/epjb/e2008-00190-1