Phase Diagram of Strongly Coupled Yukawa Particulates in Deformable Background and Application to Fine Particle (Dusty) Plasmas

We analyze thermodynamics of the system composed of charged particles with hard cores interacting via the repulsive Yukawa potential and the ambient plasma (of ions and electrons), taking the contribution of the latter properly into account. When the Coulomb coupling between particles becomes sufficiently strong, the isothermal compressibility of the whole system diverges and we have a phase separation and associated critical point. When appropriate conditions are satisfied, the critical point can be in the domain of solid phase of Yukawa particles. An enhancement of the long wavelength density fluctuations near the critical point is expected. We investigate the applicability of these results to fine particle (dusty) plasmas. Experimental conditions of fine particle plasmas, densities and temperatures of components and the fine particle size, are explicitly expressed in terms of dimensionless characteristic parameters corresponding to the critical point. Though it might be difficult to realize such a system on the ground due to large influence of the gravity on fine particles, we expect the experiment under microgravity may provide a chance of observation.