Related Experiment Video
Updated: May 24, 2026

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry
Published on: August 1, 2017
Evidence of Nonlinear Coupling in the Edge Harmonic Oscillation Sustaining Quiescent High Confinement in a Tokamak
R A Myers1,2, J S Sarff1, B E Chapman1
1University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Abstract:
In a tokamak plasma, we measure nonlinear coupling between harmonics comprising a saturated edge oscillation, as predicted by nonlinear magnetohydrodynamic simulations. The coherent structure formed by this coupling suppresses bursty edge-localized modes that cause energy and particle loss. We also measure nonlinear coupling of the edge harmonic oscillation to core-resonant magnetic tearing modes. When tearing modes are present, the edge oscillation harmonics decouple, and edge-localized modes return. We conclude that nonlinear interaction with tearing modes interrupts the formation of the edge harmonic oscillation.
Related Concept Videos
Atomic Nuclei: Nuclear Relaxation Processes
Oscillations In An LC Circuit
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
Damped Oscillations
Although friction and other non-conservative...
Forced Oscillations
Oscillations about an Equilibrium Position

