Magneto-luminescence and magneto-transport of a two-dimensional electron gas around integer filling factors

• Published in: Physica. B, Condensed matter Condensed matter, 2002-07, Vol.319 (1), p.339-342
• Main Authors: van der Meulen, H.P, Calleja, J.M, Sanchez, J, Hey, R, Friedland, K.J, Ploog, K
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in interface structures; Exact sciences and technology; Heterojunction; Integer quantum Hall effect; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Optical properties of nanoscale materials and structures; Photoluminescence; Physics; Quantum hall effect (including fractional); Two-dimensional electron gas
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/S0921-4526(02)01137-7

The magneto-optical emission of a high-mobility electron gas in a GaAs/AlGaAs single heterostructure shows a remarkable behavior near even filling factors in the quantum Hall regime. At low temperatures the light emission starts abruptly at filling factors ν=2, 4, 6, and is only observed in the presence of spin-down electrons in the last occupied Landau level (LL). For increasing magnetic field below filling factor 2, the emission energy remains essentially constant up to a critical field, after which it tends progressively to the usual LL-like behavior. Simultaneous transport measurements demonstrate that this critical field corresponds to the onset of extended states at the Fermi level, showing the same temperature dependence. The results are qualitatively interpreted as due to the formation of complex bound-states with the photo-created hole.