Origin of the effective mobility in non-linear active micro-rheology
Por:
Santamaria-Holek, I., Perez-Madrid, A.
Publicada:
7 oct 2016
Resumen:
The distinction between the damping coefficient and the effective non-linear mobility of driven particles in active micro-rheology of supercooled liquids is explained in terms of individual and collective dynamics. The effective mobility arises as a collective effect which gives insight into the energy landscape of the system. On the other hand, the damping coefficient is a constant that modulates the effect of external forces over the thermal energy which particles have at their disposition to perform Brownian motion. For long times, these thermal fluctuations become characterized in terms of an effective temperature that is a consequence of the dynamic coupling between kinetic and configurational degrees of freedom induced by the presence of the strong external force. The interplay between collective mobility and effective temperature allows to formulate a generalized Stokes-Einstein relation that may be used to determine the collective diffusion coefficient. The explicit relations we deduce reproduce simulation data remarkably well. © 2016 Author(s).
Filiaciones:
Santamaria-Holek, I.:
Univ Nacl Autonoma Mexico, UMDI Fac Ciencias, Campus Juriquilla,Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Perez-Madrid, A.:
Univ Barcelona, Dept Fis Mat Condensada, Fac Fis, Marti & Franques 1, E-08028 Barcelona, Spain
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