Dresden 2014 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
DY: Fachverband Dynamik und Statistische Physik
DY 36: Brownian Motion and Transport
DY 36.3: Vortrag
Donnerstag, 3. April 2014, 15:30–15:45, ZEU 160
Hydrodynamically enforced entropic trapping of Brownian particles — •Steffen Martens1, Gerhard Schmid2, Arthur Straube3, Lutz Schimansky-Geier3, and Peter Hänggi2 — 1Technische Universität, Berlin, Deutschland — 2Universität Augsburg, Augsburg, Deutschland — 3Humboldt-Universität zu Berlin, Berlin, Deutschland
In small systems spatial confinement causes entropic forces that in turn implies spectacular consequences for the control for mass and charge transport. In view of its importance, recent efforts in theory triggered activities which allow for an approximate description that involves a reduction of dimensionality; thus making detailed predictions tractable. Up to present days, the focus was on the role of conservative forces and its interplay with confinement. Within the presented work, we overcome this limitation and succeeded in considering also “magnetic field” like, so termed non-conservative forces that derive from a vector potential [S. Martens et al., Phys. Rev. Lett. 110, 010601 (2013)]. A relevant application is the fluid flow across microfluidic structures where a solute of Brownian particles is subject to both, an external bias and a pressure-driven flow. Then a new phenomenon emerges; namely, the intriguing finding of identically vanishing average particle flow which is accompanied by a colossal suppression of diffusion. This entropy-induced phenomenon, which we termed hydrodynamically enforced entropic trapping, offers the unique opportunity to separate particles of the same size in a tunable manner [S. Martens et al.,Eur. Phys. J. ST 222, 2453-2463 (2013)].