Fluid approach to evaluate sound velocity in Yukawa systems (complex plasmas)

Abstract

The conventional fluid description of multi-component plasma, supplemented by an appropriate equation of state for the macroparticle component, is used to evaluate the longitudinal sound velocity of Yukawa fluids. The obtained results are in very good agreement with those obtained earlier employing the quasi-localized charge approximation and molecular dynamics simulations in a rather broad parameter regime. Thus, a simple yet accurate tool to estimate the sound velocity across coupling regimes is proposed, which can be particularly helpful in estimating the dust-acoustic velocity in strongly coupled dusty (complex) plasmas. It is shown that, within the present approach, the sound velocity is completely determined by particle-particle correlations and the neutralizing medium (plasma), apart from providing screening of the Coulomb interaction, has no other effect on the sound propagation. The ratio of the actual sound velocity to its "ideal gas" (weak coupling) scale only weakly depends on the coupling strength in the fluid regime, but exhibits a pronounced decrease with the increase of the screening strength. The limitations of the present approach in applications to real complex plasmas are briefly discussed.

Physical Review E (in press)

References in corpus (3)

• Dynamical correlations and collective excitations of Yukawa liquids
• Practical expressions for the internal energy and pressure of Yukawa fluids
• Ion sphere model for Yukawa systems (dusty plasmas)

Cited by in corpus (16)

• Practical thermodynamics of Yukawa systems at strong coupling
• Collective modes in simple melts: Transition from soft spheres to the hard sphere limit
• Onset of transverse (shear) waves in strongly-coupled Yukawa fluids
• Vibrational model of thermal conduction for fluids with soft interactions
• Practical dispersion relations for strongly coupled plasma fluids
• Spontaneous generation of a temperature anisotropy in a strongly coupled magnetized plasma
• Unified description of sound velocities in strongly coupled Yukawa systems of different spatial dimensionality
• Freezing density scaling of fluid transport properties: Application to liquefied noble gases
• Fingerprints of different interaction mechanisms on the collective modes in complex (dusty) plasmas
• Dispersion relations of Yukawa fluids at weak and moderate coupling
• Ion drift instability in a strongly coupled collisional complex plasma
• Elastic properties of dense hard-sphere fluids
• Excess entropy of strongly coupled Yukawa fluids
• Description of longitudinal modes in moderately coupled Yukawa systems with the static local field correction
• Quasi-localized charge approximation approach for the nonlinear structures in strongly coupled Yukawa systems
• Variational approach to Yukawa fluids. II. Instantaneous elastic moduli and sound velocities