Two-Stage Micro-Cathode MPD Thruster and its Improvement by the Threshold Behavior of the Magnetized ARC

We propose a new concept of the low-power micro-cathode arc thruster for the cubesats – a two-stage μCAT-MPD thruster. This concept implies the preliminary production of fully-ionized metal plasma by the first stage based on pulsing vacuum arc, and subsequent acceleration of this plasma by the Lorentz force arising in the second (MPD) stage due to interaction of huge electron current in plasma and the magnetic field generated by the external coil or permanent magnet. A second stage based on applied-field magneto plasma dynamical (MPD) approach looks promising since it allows accelerating quasi-neutral plasma without using low-transparent accelerating grids, high voltages, or additional power-consumable and lifetime-limited electron sources for charge neutralization.