Experimental estimation of the dual cascade in two-dimensional drift-wave turbulence

The dual turbulent cascade is studied experimentally in two-dimensional wavenumber space. A two-field model is used for the analysis and tested on simulated data first. It is found that the energy of the turbulent fluctuations follows an inverse cascade to larger scales while enstrophy is transported in a direct cascade to smaller scales. This provides experimental evidence for the turbulent dual cascade in magnetized plasmas. The analysis also reveals the importance of non-local transfer to the cascading process.