Electrostatic particle based modeling and simulation of ultra cold plasma.

摘要

We model moderately coupled ultra cold plasma based on experimental setups and investigate the influence of external electric and magnetic fields by simulating the interaction of this plasma with constant magnetic field and radio frequency fields in the form of continuous application and short pulses. A density dependent resonant response is observed through these simulations and we infer the cause to be rapid energy transfer to individual electrons from electric fields through the collective motion of the electron cloud rather than a collision based mechanism since collisional time scales are found to be larger than the response period. It is also observed that electron evaporation influences the UCP expansion by reducing the electron temperature significantly. These arguments are corroborated by experimental results. We report diagnostics such as temperature, potential and density evolution, electron and ion pair correlation functions, and estimate the size of the UCP with varying initial ionization energies for the ultra cold plasma throughout complete simulation.