Instability-Triggered Phase Transition to a Dusty-Plasma Condensate

Abstract

Highly charged dust grains in plasma discharges reside at the sheath edge, where the ions stream toward the electrode at speed approximately c(s). Above a critical pressure P(crit), the grains lose their kinetic energy and reach a strongly coupled crystalline state, but for P <P(crit) the grains acquire a large random kinetic energy and act like a fluid. We show that the dust heating in the fluid phase is due to an ion-dust two-stream instability, which is stabilized at P >P(crit) by the combined effect of ion-molecule and grain-molecule collisions.

Dynamic Light Scattering on Complex Plasmas

“…A more comprehensive approach to explain anomalous heating caused by the wake field is described by Joyce and Ganguli et al [7,8,9]. They consider the dynamically shielded potential as described in section 3.2.1 (equation (3.23)), that is obtained by applying linear response theory.…”

“…The observations on phase transitions will be compared to the predictions of theory, in particular to the theoretical description and simulations by Joyce and Ganguli et al [7,8,9]. This work is organized as follows: Chapter 2 gives an introduction into the DLS theory.…”

“…The anisotropy of the plasma conditions in the plasma-wall sheath leads to instabilities that are responsible for the extreme heating of the dust particle component [5,6,7,8,9].…”

Simulations of the dust acoustic instability in a collisional plasma with warm dust

“…While the reason for the large dust kinetic temperature is not definitively known, theories for dust heating have been proposed, including dust heating by wave-particle interactions (e.g. Schweigert et al 1996;Joyce et al 2002). In addition, numerical particle-in-cell (PIC) simulations have shown that dust can get heated by waves in the nonlinear development of the ion-dust streaming instability Winske & Rosenberg 1998;Winske 2004;Fu & Scales 2012).…”

“…Rosenberg 1993) or, more generally, an ion-dust streaming instability, which also includes the case when the ion flow is superthermal (e.g. Rosenberg 1996;Joyce, Lampe & Ganguli 2002).…”