Investigation of silicon heterojunction solar cells by photoluminescence under DC-bias Guillaume Courtois, Parsathi Chatterjee, Veinardi Suendo, Antoine Salomon and Pere Roca i Cabarrocas EPJ Photovolt., 4 (2013) 45106 Published online: 27 September 2013 DOI: 10.1051/epjpv/2013022