Nonlinear interactions, heating and turbulence associated with large amplitude Alfv\'{e}n waves in a laboratory plasma

From a weak turbulence point of view, nonlinear interactions between shear Alfv\'{e}n waves are fundamental to the turbulent energy cascade in magnetic turbulence. Motivated by this, experiments on the interaction between large amplitude Alfv\'{e}n waves are being carried out on the the Large Plasma Device (LAPD) at UCLA. Large amplitude Alfv\'{e}n waves ($\delta B/B \sim 1$\%) are generated either using a resonant cavity (the Alfv\'{e}n wave MASER\footnote{J.E. Maggs and G.J. Morales, Phys. Rev. Lett. {\bfseries 91}, 035004 (2003)}) or loop antennas. Nonlinear interactions between two copropagating kinetic Alfv\'{e}n waves have been observed\footnote{T.A. Carter, B. Brugman, {\itshape et. al}, Phys. Rev. Lett. {\bfseries 96}, 15501 (2006)}. Strong, localized electron heating during large amplitude kinetic Alfv\'{e}n wave launch is also observed. The heating results in significant gradients in the electron temperature which in turn excite unstable drift-Alfv\'{e}n waves. The drift waves then interact with the initial Alfv\'{e}n wave, leading to sidebands and spectral broadening. Details of these experimental observations will be discussed, as well as future plans for studies of nonlinear processes assocaiuted with Alfv\'{e}n waves in LAPD.