title: Spatiotemporal splitting of global eigenmodes due to cross-field coupling via vortex dynamics in drift wave turbulence.
abstract: Spatiotemporal splitting events of drift wave (DW) eigenmodes due to nonlinear coupling are investigated in a cylindrical helicon plasma device. DW eigenmodes in the radial-azimuthal cross section have been experimentally observed to split at radial locations and recombine into the global eigenmode with a time shorter than the typical DW period (t≪fDW(-1)). The number of splits correlates with the increase of turbulence. The observed dynamics can be theoretically reproduced by a Kuramoto-type model of a network of radially coupled azimuthal eigenmodes. Coupling by E×B-vortex convection cell dynamics and ion gyro radii motion leads to cross-field synchronization and occasional mode splitting events.
authors.affiliation: Center for Energy Research, University of California-San Diego, La Jolla, California 92093-0417, USA.
authors.forename: C
authors.initials: C
authors.lastname: Brandt
authors.affiliation: Center for Energy Research, University of California-San Diego, La Jolla, California 92093-0417, USA and Center for Momentum Transport and Flow Organization, La Jolla, California 92093-0417, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Thakur
authors.affiliation: Center for Momentum Transport and Flow Organization, La Jolla, California 92093-0417, USA and Center for Integrated Plasma Studies, Department of Physics, University of Colorado at Boulder, Boulder, Colorado 80309, USA.
authors.forename: A D
authors.initials: AD
authors.lastname: Light
authors.affiliation: Max-Planck-Institut für Dynamik und Selbstorganisation (MPIDS), Am Faßberg 17, 37077 Göttingen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Negrete
authors.affiliation: Center for Energy Research, University of California-San Diego, La Jolla, California 92093-0417, USA and Center for Momentum Transport and Flow Organization, La Jolla, California 92093-0417, USA.
authors.forename: G R
authors.initials: GR
authors.lastname: Tynan