title: Exchange control of nuclear spin diffusion in a double quantum dot.
abstract: The influence of gate-controlled two-electron exchange on the relaxation of nuclear polarization in small ensembles (N∼10(6)) of nuclear spins is examined in a GaAs double quantum dot system. Waiting in the (2,0) charge configuration, which has large exchange splitting, reduces the nuclear diffusion rate compared to that of the (1,1) configuration. Matching exchange to Zeeman splitting significantly increases the nuclear diffusion rate.
authors.affiliation: Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Reilly
authors.forename: J M
authors.initials: JM
authors.lastname: Taylor
authors.forename: J R
authors.initials: JR
authors.lastname: Petta
authors.forename: C M
authors.initials: CM
authors.lastname: Marcus
authors.forename: M P
authors.initials: MP
authors.lastname: Hanson
authors.forename: A C
authors.initials: AC
authors.lastname: Gossard