title: Energy-level structure of two-dimensional electrons confined at the AlxGa1-xAs/GaAs interface studied by photoluminescence excitation spectroscopy.
authors.initials: QX
authors.lastname: Zhao
authors.initials: Y
authors.lastname: Fu
authors.initials: PO
authors.lastname: Holtz
authors.initials: B
authors.lastname: Monemar
authors.initials: JP
authors.lastname: Bergman
authors.initials: KA
authors.lastname: Chao
authors.initials: M
authors.lastname: Sundaram
authors.initials: JL
authors.lastname: Merz
authors.initials: AC
authors.lastname: Gossard