Research
Plasmas generated from an ECR source
Electron Cyclotron Resonance (ECR) source & applications: ECR using microwave is a very efficient mean to generate low pressure high density plasmas in laboratory. ECR requires an external strong magnetic field ( ~ 875 G for 2.45 GHz) which plays important role in designing the source since the plasma transport inside the source is highly affected by the field orientation. Our group is currently exploring on the following applications utilizing an ECR source developed at the lab.
•Plasma Thruster: We are currently in process of evaluating performance of an ECR source based electrode less plasma thruster developed in the lab. Electrode-less plasma thruster is future technology which can be used for orbital correction of satellites and deep space propulsion. Leading technologies like Hall and Ion thrusters use electrodes and neutralizers which limits the lifetime of the thruster.
•Negative Hydrogen ion source: Negative hydrogen ion beam finds major application for production of high energy neutral beam required for heating of thermonuclear fusion plasmas. A large volume ECR based plasma system is currently under investigation for efficient production of negative ions (H-) in hydrogen plasmas.
Plasma Spectroscopy: It is a powerful diagnostic tool for analyzing the plasma species and determining the plasma parameters. It is mostly non-intrusive in nature unlike the electric probes. We have following spectroscopic diagnostics equipped with high end instruments.
•Laser induced Fluorescence (LIF) spectroscopy: It is used determine the ion velocities and its distribution utilizing the Laser induced Fluorescence (LIF) spectroscopy. For this purpose a tunable diode laser is used to excite the plasma ions at the Doppler shifted frequency.
•Emission Spectroscopy: A high resolution (~ 6 pm) spectrometer is used for plasma optical emission spectroscopy. The high resolution enabled to resolve even the molecular bands in case of molecular gas plasma (like hydrogen or atmospheric pressure plasma).
The tunable diode laser used for the LIF
Double Plasma Machine Set up. (Inset) A glowing filament inside the DP machine
Basic Research: Plasma is a complex medium containing several charged and neutral species. How these species interact among themselves or responds to external field and wave are still subject of investigation which can lead to understand many natural phenomena, improve performance of plasma based applications and lead path to future applications. We have a double plasma machine in our lab to cater basic researches related to different kind of wave propagation , instabilities, double layers etc.