title: Effects of inversion asymmetry on electron-nuclear spin coupling in semiconductor heterostructures: possible role of spin-orbit interactions.
abstract: We show that electron-nuclear spin coupling in semiconductor heterostructures is strongly modified by their potential inversion asymmetry. This is demonstrated in a GaAs quantum well, where we observe that the current-induced nuclear spin polarization at Landau-level filling factor nu=2/3 is completely suppressed when the quantum well is made largely asymmetric with gate voltages. Furthermore, we find that the nuclear spin relaxation rate is also modified by the potential asymmetry. These findings strongly suggest that even a very weak Rashba spin-orbit interaction can play a dominant role in determining the electron-nuclear spin coupling.
authors.affiliation: NTT Basic Research Laboratories, NTT Corporation, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan.
authors.forename: Katsushi
authors.initials: K
authors.lastname: Hashimoto
authors.forename: Koji
authors.initials: K
authors.lastname: Muraki
authors.forename: Norio
authors.initials: N
authors.lastname: Kumada
authors.forename: Tadashi
authors.initials: T
authors.lastname: Saku
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Hirayama