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Entropons as collective excitations in active solids.

Lorenzo Caprini1, Umberto Marini Bettolo Marconi2,3, Andrea Puglisi4,5

  • 1Heinrich-Heine-Universität Düsseldorf, Institut für Theoretische Physik II-Weiche Materie, D-40225 Düsseldorf, Germany.

The Journal of Chemical Physics
|July 24, 2023
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Summary
This summary is machine-generated.

Researchers discovered new vibrational excitations called "entropons" in active solids. These novel modes, arising from non-equilibrium physics, dominate over traditional phonons in systems far from equilibrium.

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Area of Science:

  • Condensed Matter Physics
  • Non-equilibrium Statistical Mechanics
  • Soft Matter Physics

Background:

  • Vibrational dynamics in equilibrium crystals are explained by phonons.
  • Active solids, composed of self-propelled particles, exist in a non-equilibrium steady-state.

Purpose of the Study:

  • To identify and characterize novel vibrational collective excitations in non-equilibrium active solids.
  • To interpret these excitations within the framework of non-equilibrium physics and stochastic thermodynamics.

Main Methods:

  • Theoretical analysis of vibrational collective excitations in active solids.
  • Framework of non-equilibrium physics and stochastic thermodynamics.

Main Results:

  • Identification of novel vibrational collective excitations of non-equilibrium origin, termed 'entropons'.
  • These 'entropons' coexist with phonons but dominate when the system is far from equilibrium.
  • Entropons are characterized as modes of spectral entropy production.

Conclusions:

  • Entropons represent a new class of vibrational excitations unique to active, non-equilibrium systems.
  • The findings offer a new perspective on understanding energy dissipation and collective behavior in active matter.
  • Experimental verification is proposed in systems like active colloids, granular matter, and cell monolayers.