Université de Fribourg

Brownian systems with spatially inhomogeneous activity

Sharma, Abhinav ; Brader, Joseph M.

In: Physical Review E, 2017, vol. 96, no. 3, p. 032604

We generalize the Green-Kubo approach, previously applied to bulk systems of spherically symmetric active particles [J. Chem. Phys. 145, 161101 (2016)], to include spatially inhomogeneous activity. The method is applied to predict the spatial dependence of the average orientation per particle and the density. The average orientation is given by an integral over the self part of the Van Hove...

Université de Fribourg

Escape rate of active particles in the effective equilibrium approach

Sharma, Abhinav ; Wittmann, René ; Brader, Joseph M.

In: Physical Review E, 2017, vol. 95, no. 1, p. 012115

The escape rate of a Brownian particle over a potential barrier is accurately described by the Kramers theory. A quantitative theory explicitly taking the activity of Brownian particles into account has been lacking due to the inherently out-of-equilibrium nature of these particles. Using an effective equilibrium approach [Farage et al., Phys. Rev. E 91, 042310 (2015)] we study the escape...

Université de Fribourg

Strain-driven criticality underlies nonlinear mechanics of fibrous networks

Sharma, Abhinav ; Licup, A. J. ; Rens, R. ; Vahabi, M. ; Jansen, K. A. ; Koenderink, G. H. ; MacKintosh, F. C.

In: Physical Review E, 2016, vol. 94, no. 4, p. 042407

Networks with only central force interactions are floppy when their average connectivity is below an isostatic threshold. Although such networks are mechanically unstable, they can become rigid when strained. It was recently shown that the transition from floppy to rigid states as a function of simple shear strain is continuous, with hallmark signatures of criticality [Sharma et al., Nature...

Université de Fribourg

Green-Kubo approach to the average swim speed in active Brownian systems

Sharma, Abhinav ; Brader, Joseph M.

In: The Journal of Chemical Physics, 2016, vol. 145, no. 16, p. 161101