Fractional quantum hall effect in second subband of a 2DES - Duarte, Celso de Araujo; Armas, Luis Enrique Gomes; Bakarov, Askhat K; Wiedmann, Steffen Robert; Silva, Euzi Conceição Fernandes da; Gusev, Guennadii Michailovich; Portal, Jean-Claude (Brazilian Workshop on Semiconductor Physics, 2011)