Comparing the luminescence of ZnS:Mn/CdS:Mn quantum dots M. H. Yousefi, A. A. Khosravi, K. Rahimi and A. Nazesh Eur. Phys. J. Appl. Phys., 45 1 (2009) 10602 Published online: 16 January 2009 DOI: 10.1051/epjap:2008199