Extended self-similarity in two-dimensional complex plasmas

Abstract

Self-similarity is a property of an object or process wherein a part is similar to the whole. Mathematically, it can often be expressed as a power-law scaling of the quantity of interest. Extended self-similarity is a concept widely used in the field of turbulence and refers to the power-law scaling of the longitudinal structure functions of the velocity field expressed through the structure functions of different orders, rather than distance. Originally discovered by [R. Benzi et al., Phys. Rev. E 48, R29 (1993)] in fully developed turbulence, it was later found to hold in other situations and systems as well. In this paper, we show that in an active-matter system, extended self-similarity is possible even without the presence of respective power-law scaling in the underlying structure functions of distance. The active-matter system used in this study was a single-layer suspension of active Janus particles in a plasma. Janus particles are polymer microspheres with hemispherical metal coating. When dispersed in a plasma, they acquire self-propulsion and act as microswimmers. Extended self-similarity was also observed in the velocity field of a single-layer suspension of laser-heated regular (passive) particles, where the underlying structure functions displayed a hint of the power-law scaling near the mean interparticle distance. Therefore, it appears to be an inherent characteristic of complex plasmas.

arXiv comment6 pages, 4 figures

References in corpus (16)

• Active Particles in Complex and Crowded Environments
• Physics of Microswimmers - Single Particle Motion and Collective Behavior
• Active Turbulence
• Shear Flows and Shear Viscosity in a Two-Dimensional Yukawa System (Dusty Plasma)
• Direct observation of mode-coupling instability in two-dimensional plasma crystals
• Wave mode coupling due to plasma wakes in two-dimensional plasma crystals: In-depth view
• Static and dynamic shear viscosity of a single layer complex plasma
• Active Janus particles in a complex plasma
• Kolmogorovian active turbulence of a sparse assembly of interacting swimmers
• Volatility, Persistence, and Survival in Financial Markets
• Extended Self Similarity works for the Burgers equation and why
• Intermittency, fluctuations and maximal chaos in an emergent universal state of active turbulence
• Stability of two-dimensional complex plasma monolayers in asymmetric capacitively-coupled radio-frequency discharges
• A new scaling property of turbulent flows
• Two-dimensional complex (dusty) plasma with active Janus particles
• Extended self-similarity of atmospheric boundary layer wind fields in mesoscale regime: Is it real?