Magnetized Linear Plasma Device – Inverse Mirror Plasma Experimental Device (IMPED)

The device is built to serve as a laboratory testbed for investigating fundamental plasma physics of nonlinear plasma waves and instabilities. It is designed to bridge the gap between the theoretical predictions and experimental verification of the complex plasma phenomena such as wave-breaking, energy cascading and formation of coherent structures like Zonal flows and Streamers. These are critical for both laboratory fusion research and astrophysical observations.

1. Superior Quiescence: IMPED has achieved a high degree of plasma quiescence, with background density fluctuations as low as 0.5%. This level of stability is mandatory for studying the onset of subtle nonlinear phenomena like wave breaking and phase mixing.
2. Advanced Diagnostics and Automation: The facility utilizes an automated plasma probing system with 0.2 mm positioning accuracy and high-speed (1 MHz) PXIe-based data acquisition.
3. Instability Dynamics: To explore the parametric existence of the nonlinear interactions of primary instabilities including Drift Waves, Rayleigh-Taylor and Kelvin-Helmholtz modes. Energy transfer dynamics across instabilities during non-linear interactions.

Major activities ongoing and planned activities:

1. Turbulence and Transport Regulations: To understand how energy is redistributed across scales and how large-scale structures like zonal flows and streamers emerge to regulate anomalous particle transport.
2. Zonal Flow Control, Modulation and Damping: Identifying the suitable knobs to control the excitation, modulation and damping of zonal flows will be carried out.
3. Energy Transfer Analysis: Development of an analysis tool to investigate the energy transfer across different modes of turbulent spectrum, benchmarking of the code and application of higher-order spectral tools to determine the direction of nonlinear energy transfer between different plasma modes.
4. Turbulence Transition: Controlled transition of plasma turbulence, coherent structures, interaction between zonal flow and mean flow will be investigated. Systematic investigation leading to emergence of zonal flows and transition to streamers and nonlinear coherent structures like Cnoidal waves will be attempted.
5. Comprehensive Wave Studies: To perform controlled investigations into the phase mixing and wave breaking of nonlinear plasma oscillations, identifying the limits of wave amplitudes that a plasma can sustain.