title: Nature of the spin transition in the half-filled Landau level.
abstract: We report transport and nuclear spin relaxation studies of a density tunable two-dimensional electron system at filling nu=1/2 in tilted magnetic fields. The transition from partial to full spin polarization with an in-plane field leaves a clear signature in the resistance. Nuclear spin relaxation studies suggest that puddles of minority spins are responsible for an observed non-Korringa temperature dependence. This inhomogeneous spin polarization, similarly encountered in manganites where it strongly affects resistance, may help with understanding the spin dependent transport at nu=1/2.
authors.affiliation: Max-Planck-Institute for Solid State Research, Heisenbergstrasse 1, D-70569, Stuttgart, Germany.
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Li
authors.forename: V
authors.initials: V
authors.lastname: Umansky
authors.forename: K
authors.initials: K
authors.lastname: von Klitzing
authors.forename: J H
authors.initials: JH
authors.lastname: Smet