Reversible spin-optical interface in luminescent organic radicals by Gorgon, S, Lv, K, Grüne, J, Drummond, BH, Myers, WK, Londi, G, Ricci, G, Valverde, D, Tonnelé, C, Murto, P, Romanov, AS, Casanova, D, Dyakonov, V, Sperlich, A, Beljonne, D, Olivier, Y, Li, F, Friend, RH, Evans, EW