Non-equilibrium work distribution for interacting colloidal particles under friction

Abstract

We experimentally investigate the non-equilibrium steady-state distribution of the work done by an external force on a mesoscopic system with many coupled degrees of freedom: a colloidal crystal mechanically driven across a commensurate periodic light field. Since this system mimics the spatiotemporal dynamics of a crystalline surface moving on a corrugated substrate, our results show general properties of the work distribution for atomically flat surfaces undergoing friction. We address the role of several parameters which can influence the shape of the work distribution, e.g. the number of particles used to locally probe the properties of the system and the time interval to measure the work. We find that, when tuning the control parameters to induce particle depinning from the substrate, there is an abrupt change of the shape of the work distribution. While in the completely static and sliding friction regimes the work distribution is Gaussian, non-Gaussian tails show up due to the spatiotemporal heterogeneity of the particle dynamics during the transition between these two regimes.

Application of the Self-Organization Phenomenon in the Development of Wear Resistant Materials—A Review

“…As applied to sliding electric contacts this implies an increase of velocity of the reactions (8) and (9). Increasing the reactions' velocity enables an increase of absolute value at the negative part of the production of entropy and to reduce the overall production of entropy in Equation (7).…”

“…Over the past several years there have been many scientific publications regarding the application of nonequilibrium thermodynamics and the theory of self-organization in tribology, for instance [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Normally articles on nonequilibrium thermodynamics as applied to friction are divided into two types.…”

“…However, the authors of [1] fail to define what self-organization actually means. In [9] nonequilibrium stationary distribution of work performed by external forces over a mesoscopic system with multiple degrees of freedom is reviewed. The recommendations for applying the results achieved are not presented in [9].…”

“…In [9] nonequilibrium stationary distribution of work performed by external forces over a mesoscopic system with multiple degrees of freedom is reviewed. The recommendations for applying the results achieved are not presented in [9]. In [10] it is proposed to use the second law of thermodynamics in order to determine the tribosystem's degradation (accumulation of defects and damages).…”

Focus on stochastic thermodynamics

“…Sasa shows how the emerging collective dynamics in such systems at the transition can be determined and interpreted using concepts from stochastic and steady-state thermodynamics [24]. Experimental results for the work distribution of interacting colloidal particles forming a colloidal crystal that is driven across a commensurate periodic light field are presented by Gomez-Solano et al  [25]. Transport in interacting systems is studied by Becker et al for a boundary driven set-up, for which they show simulations that support predictions from macroscopic fluctuation theory and the additivity principle [26].…”