We numerically investigate the trapping behaviors of aligning particles in two-dimensional(2 D) random obstacles system. Under the circumstances of the effective diffusion rate and the average velocity tend to zero, p...We numerically investigate the trapping behaviors of aligning particles in two-dimensional(2 D) random obstacles system. Under the circumstances of the effective diffusion rate and the average velocity tend to zero, particles are in trapped state. In this paper, we examine how the system parameters affect the trapping behaviors. At the large self-propelled speed, the ability of nematic particles escape from trapping state is enhancing rapidly, in the meanwhile the polar and free particles are still in trapped state. For the small rotation diffusion coefficient, the polar particles circle around(like vortices)the obstacles and here particles are in trapped state. Interestingly, only the partial nematic particles are trapped in the confined direction and additional particles remain flowing. In the free case, the disorder particle–particle collisions impede the motion in each other's directions, leading the free particles to be trapped. At the large rotation diffusion coefficient,the ordered motion of aligning particles disappear, particles fill the sample evenly and are self-trapped around obstacles.As the particles approach the trapping density due to the crowding effect the particles become so dense that they impede each other's motion. With the increasing number of obstacles, the trajectories of particles are blocked by obstacles, which obstruct the movement of particles. It is worth noting that when the number of the obstacles are large enough, once the particles are trapped, the system is permanently absorbed into a trapped state.展开更多
We studied the rectified transport of underdamped particles subject to phase lag in an asymmetric periodic structure.When the inertia effect is considered,it is possible to observe reversals of the average velocity wi...We studied the rectified transport of underdamped particles subject to phase lag in an asymmetric periodic structure.When the inertia effect is considered,it is possible to observe reversals of the average velocity with small self-propelled force,whereas particles always move in the positive direction with large self-propelled force.The introduction of phase lag leads particles to follow circular orbits and suppress the polar motion.In addition,this can adjust the direction of particle motion.There exists an optimal value of polar interaction strength at which the rectification is maximal.These results open the way for many application processes,such as spatial sorting of particles mixture and separation based on their physical properties.展开更多
Ratchet transport of overdamped particles is investigated in superimposed driven lattices using Langevin dynamics simulations. It is found that noise can strongly affect the transport of the particles. When lattices d...Ratchet transport of overdamped particles is investigated in superimposed driven lattices using Langevin dynamics simulations. It is found that noise can strongly affect the transport of the particles. When lattices driving dominates the transport, the noise acts as a disturbance of the directed transport and slows down the average velocity of the particles.When the driving phase has less impact on particle transport, Gaussian white noise can play a positive role. By simply modulating these two parameters, we can control efficiency and the direction of the directed currents.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11575064 and 11175067)the PCSIRT(Grant No.IRT1243)+1 种基金the GDUPS(2016)the Natural Science Foundation of Guangdong Province,China(Grant No.2014A030313426)
文摘We numerically investigate the trapping behaviors of aligning particles in two-dimensional(2 D) random obstacles system. Under the circumstances of the effective diffusion rate and the average velocity tend to zero, particles are in trapped state. In this paper, we examine how the system parameters affect the trapping behaviors. At the large self-propelled speed, the ability of nematic particles escape from trapping state is enhancing rapidly, in the meanwhile the polar and free particles are still in trapped state. For the small rotation diffusion coefficient, the polar particles circle around(like vortices)the obstacles and here particles are in trapped state. Interestingly, only the partial nematic particles are trapped in the confined direction and additional particles remain flowing. In the free case, the disorder particle–particle collisions impede the motion in each other's directions, leading the free particles to be trapped. At the large rotation diffusion coefficient,the ordered motion of aligning particles disappear, particles fill the sample evenly and are self-trapped around obstacles.As the particles approach the trapping density due to the crowding effect the particles become so dense that they impede each other's motion. With the increasing number of obstacles, the trajectories of particles are blocked by obstacles, which obstruct the movement of particles. It is worth noting that when the number of the obstacles are large enough, once the particles are trapped, the system is permanently absorbed into a trapped state.
基金Project supported by the National Natural Science Foundation of China(Grant No.12075090)the Key-Area Research and Development Program of Guangdong Province,China(Grant No.2019B030330001)+2 种基金the Science and Technology Program of Guangzhou City(Grant No.2019050001)the Natural Science Foundation of Guangdong Province,China(Grant No.2017A030313029)the Major Basic Research Project of Guangdong Province,China(Grant No.2017KZDXM024)。
文摘We studied the rectified transport of underdamped particles subject to phase lag in an asymmetric periodic structure.When the inertia effect is considered,it is possible to observe reversals of the average velocity with small self-propelled force,whereas particles always move in the positive direction with large self-propelled force.The introduction of phase lag leads particles to follow circular orbits and suppress the polar motion.In addition,this can adjust the direction of particle motion.There exists an optimal value of polar interaction strength at which the rectification is maximal.These results open the way for many application processes,such as spatial sorting of particles mixture and separation based on their physical properties.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11575064 and 11175067)the PCSIRT(Grant No.IRT1243)+2 种基金the GDUPS Project(2016)the Natural Science Foundation of Guangdong Province,China(Grant Nos.2016A030313433 and 2017A030313029)the Innovation Project of Graduate School of South China Normal University
文摘Ratchet transport of overdamped particles is investigated in superimposed driven lattices using Langevin dynamics simulations. It is found that noise can strongly affect the transport of the particles. When lattices driving dominates the transport, the noise acts as a disturbance of the directed transport and slows down the average velocity of the particles.When the driving phase has less impact on particle transport, Gaussian white noise can play a positive role. By simply modulating these two parameters, we can control efficiency and the direction of the directed currents.