ترغب بنشر مسار تعليمي؟ اضغط هنا

Giant Negative Mobility of Janus Particles in a Corrugated Channel

187   0   0.0 ( 0 )
 نشر من قبل Pulak Kumar Ghosh Dr.
 تاريخ النشر 2014
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

We numerically simulate the transport of elliptic Janus particles along narrow two-dimensional channels with reflecting walls. The self-propulsion velocity of the particle is oriented along either their major (prolate) or minor axis (oblate). In smooth channels, we observe long diffusion transients: ballistic for prolate particles and zero-diffusion for oblate particles. Placed in a rough channel, prolate particles tend to drift against an applied drive by tumbling over the wall protrusions; for appropriate aspect ratios, the modulus of their negative mobility grows exceedingly large (giant negative mobility). This suggests that a small external drive suffices to efficiently direct self-propulsion of rod-like Janus particles in rough channels.



قيم البحث

اقرأ أيضاً

Brownian transport of self-propelled overdamped microswimmers (like Janus particles) in a two-dimensional periodically compartmentalized channel is numerically investigated for different compartment geometries, boundary collisional dynamics, and part icle rotational diffusion. The resulting time-correlated active Brownian motion is subject to rectification in the presence of spatial asymmetry. We prove that ratcheting of Janus particles can be orders of magnitude stronger than for ordinary thermal potential ratchets and thus experimentally accessible. In particular, autonomous pumping of a large mixture of passive particles can be induced by just adding a small fraction of Janus particles.
128 - Pulak Kumar Ghosh 2014
We numerically investigate the escape kinetics of elliptic Janus particles from narrow two-dimensional cavities with reflecting walls. The self-propulsion velocity of the Janus particle is directed along either their major (prolate) or minor axis (ob late). We show that the mean exit time is very sensitive to the cavity geometry, particle shape and self-propulsion strength. The mean exit time is found to be a minimum when the self-propulsion length is equal to the cavity size. We also find the optimum mean escape time as a function of the self-propulsion velocity, translational diffusion, and particle shape. Thus, effective transport control mechanisms for Janus particles in a channel can be implemented.
The transport of self-propelled particle confined in corrugated channel with L{e}vy noise is investigated. The parameters of L{e}vy noise(i.e., the stability index, the asymmetry parameter, the scale parameter, the location parameter) and the paramet ers of confined corrugated channel(i.e., the compartment length, the channel width and the bottleneck size) have joint effects on the system. There exits flow reverse phenomena with increasing mean parameter. Left distribution noise will induce $-x$ directional transport and right distribution noise will induce $+x$ directional transport. The distribution skewness will effect the moving direction of the particle. The average velocity shows complex behavior with increasing stability index. The angle velocity and the angle Gaussian noise have little effects on the particle transport.
147 - Chia-Lung Hsieh 2013
Supported lipid bilayers have been studied intensively over the past two decades. In this work, we study the diffusion of single gold nanoparticles (GNPs) with diameter of 20 nm attached to GM1 ganglioside or DOPE lipids at different concentrations i n supported DOPC bilayers. The indefinite photostability of GNPs combined with the high sensitivity of interferometric scattering microscopy (iSCAT) allows us to achieve 1.9 nm spatial precision at 1 ms temporal resolution, while maintaining long recording times. Our trajectories visualize strong transient confinements within domains as small as 20 nm, and the statistical analysis of the data reveals multiple mobilities and deviations from normal diffusion. We present a detailed analysis of our findings and provide interpretations regarding the effect of the supporting substrate and GM1 clustering. We also comment on the use of high-speed iSCAT for investigating diffusion of lipids, proteins or viruses in lipid membranes with unprecedented spatial and temporal resolution.
We investigate the transport diffusivity of artificial microswimmers, a.k.a. Janus particles, moving in a sinusoidal channel in the absence of external biases. Their diffusion constant turns out to be quite sensitive to the self-propulsion mechanism and the geometry of the channel compartments. Our analysis thus suggests how to best control the diffusion of active Brownian motion in confined geometries.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا