Enhancement of the decay rate by plasmon coupling for Eu3+ in an Au nanoparticle model system J. T. van Wijngaarden, M. M. van Schooneveld, C. de Mello Donegá and A. Meijerink EPL, 93 5 (2011) 57005 Published online: 09 March 2011 DOI: 10.1209/0295-5075/93/57005