Circularly Polarized Photoluminescence as a Probe of Density of States in GaAs/AlGaAs Quantum Hall Bilayers

Polarized magnetophotoluminescence is employed to study the energies and occupancies of four lowest Landau levels in a couple quantum Hall GaAs/AlGaAs double quantum well. As a result, a magnetic field-induced redistribution of charge over the Landau levels manifesting to the continuous formation of the charge density wave and direct evidence for the symmetric-antisymmetric gap shrinkage at v = 3 are found. The observed interlayer charge exchange causes depolarization of the ferromagnetic ground state.FAPESPCNPqNHMFL-UCGPFSUEEIGState of FloridaState of FloridaDOEDOE[NSF/DMR-0654118

Quantum oscillations of spin polarization in a GaAs/AlGaAs double quantum well

5 We employ the circular-polarization-resolved magnetophotoluminescence technique to probe the spin character of electron and hole states in a GaAs/AlGaAs strongly coupled double-quantum-well system. The photoluminescence (PL) intensities of the lines associated with symmetric and antisymmetric electron states present clear out-of-phase oscillations between integer values of the filling factor. and are caused by magnetic-field-induced changes in the population of occupied Landau levels near to the Fermi level of the system. Moreover, the degree of circular polarization of these emissions also exhibits the oscillatory behavior with increasing magnetic field. Both quantum oscillations observed in the PL intensities and in the degree of polarizations may be understood in terms of a simple single-particle approach model. The k . p method was used to calculate the photoluminescence peak energies and the degree of circular polarizations in the double-quantum-well structure as a function of the magnetic field. These calculations prove that the character of valence band states plays an important role in the determination of the degree of circular polarization and, thus, resulting in a magnetic-field-induced change of the polarization sign.FAPESPFAPESPCNPqCNPqNHMFL-UCGPNHMFLUCGPFSU-EEIGFSUEEIGState of FloridaState of FloridaDOEDOE[NSF/DMR-0654118

A regulação emocional, autoconsciência e satisfação com a vida em jovens institucionalizados e não institucionalizados

A literatura científica tem evidenciado que a capacidade de regulação emocional e a autoconsciência estão presentes no funcionamento adaptativo ou psicopatológico, contudo a influência dessas variáveis na satisfação com a vida tem sido pouco estudada teoricamente. Neste estudo pretende-se analisar a relação dessas variáveis, da regulação emocional, autoconsciência e satisfação com a vida com as características da amostra, género, idade e institucionalização. Participaram no estudo 47 jovens tanto institucionalizados como não institucionalizados, de ambos os sexos. Foram administrados, a todos os participantes, dois instrumentos sendo eles a escala Emotion Regulation Index for Children and Adolescents (ERICA) traduzida e aferida para a população portuguesa por Reverendo e Machado (2011) e a escala Satisfaction With Life Scale (SWLS) traduzida e aferida para a população portuguesa por Simões (1992) para avaliar a capacidade de regulação emocional e a satisfação com a vida. A satisfação com a vida não apresentou diferenças significativas quanto às variáveis independentes, já a regulação emocional demonstrou diferenças significativas quanto ao género, salientando-se o feminino. Os resultados revelam-se promissores ao nível da compreensão da capacidade de regulação emocional, autoconsciência e satisfação com a vida.The scientific literature has evidenced that emotional regulation and self-awareness are present in adaptive or psychopathological functioning; however there is a dearth of literature about the influence of these variables in life satisfaction. This study aims to analyze the relation of these variables, emotional adjustment, self-awareness and life satisfaction with the characteristics of the sample, gender, age and institutionalization. Participated in the study 47 young both institutionalized as not institutionalized, of both sexes. Were administered to all participants, two instruments being they scale Emotion Regulation Index for Children and Adolescents (ERICA) translated and checked for the Portuguese population by Reverendo and Machado (2011) and the Satisfaction With Life Scale (SWLS) translated and checked for the Portuguese population by Sen (1992) to assess the ability of emotional adjustment and satisfaction with life. Life satisfaction showed no significant differences concerning independent variables, although emotional regulation demonstrated significant differences concerning gender, specifically female. The results are promising in terms of understanding the emotional adjustment capacity, self-awareness and life satisfaction. KEYWORDS: Children and adolescents; Emotion