Critical point and sound waves in complex plasmas

Abstract

An equation of state for particles in complex plasmas, which includes contributions from plasma background fields and interparticle interactions (electric repulsion and “ion shadow” attraction), is obtained. Using this equation, experimental parameter regimes for the observation of liquid-vapor transitions and a critical point are examined. In addition, it is demonstrated that as in binary fluids, sound waves in complex plasmas do not exhibit critical behavior. Thus, criticality in complex plasmas may have more in common with binary fluids rather than ordinary fluids.