The physics and applications of strongly coupled plasmas levitated in electrodynamic traps

Abstract

Charged (nano)particles confined in electrodynamic traps can evolve into strongly correlated Coulomb systems which are the subject of current investigation. Exciting physical phenomena associated to Coulomb systems are reported such as autowave generation, phase transitions, defect formation, system self-locking at the edges of a linear Paul trap, self-organization in layers, or pattern formation and scaling. We investigate the dynamics of ordered structures consisting of highly nonideal similarly charged nanoparticles with coupling parameter of the order $\Gamma = 10^8$. This approach enables us to study the interaction of nanoparticle structures in presence and in absence of the neutralizing plasma background, as well as to investigate various types of phenomena and physical forces experienced by these structures. We review applications of electrodynamic levitation for mass spectrometry including containment and study of single aerosols and nanoparticles, with an emphasis on state of the art experiments and techniques, while also focusing on future trends and directions of investigation. Late experimental data suggest that inelastic scattering can be successfully applied to the detection of biological particles such as pollen, bacteria, aerosols, traces of explosives or synthetic polymers. Brownian dynamics is used to characterize charged particle evolution in time and thus identify regions of stable trapping. An analytical model is used to explain the experimental results. Numerical simulations take into account the stochastic forces of random collisions with neutral particles, the viscosity of the gas medium, regular forces produced by the a.c. trapping voltage and the gravitational force. Laser plasma acceleration of charged particles is also discussed, with an emphasize on dielectric capillaries and Paul traps employed for target micropositioning.