Description
The interaction between energetic-particle-driven instabilities and self-generated zonal flows represents a frontier in the physics of burning plasmas, where alpha-particle populations dominate the system dynamics. This study identifies an intrinsic, self-organized coupling between Alfvénic turbulence and low-frequency zonal flows (LFZFs) that provides a mechanism for the mitigation of edge-localized modes (ELMs). It is observed that ELM-induced fast-ion redistribution triggers a broadband Alfvénic turbulence (100–150 kHz), with an onset delay that is inversely proportional to the ELM amplitude. Bispectral analysis demonstrates a significant nonlinear three-wave interaction wherein this Alfvénic turbulence drives the growth of LFZFs. The resulting zonal flows act as a regulatory shear layer, shortening the radial correlation length of the turbulence and effectively suppressing ELM-induced energy transport. This finding suggests a new perspective on edge stability control, rather than relying on external actuators, it reveals that the energetic particle in future fusion reactors can be harnessed to self-mitigate large-scale instabilities. These results provide a critical physical framework for achieving high-conformance operation in the burning plasma era, ensuring the protection of plasma-facing components through intrinsic, self-regulating plasma processes. This work has been submitted to Physical Review Letters.