Double-temperature ratchet model and current reversal of coupled Brownian motors

Abstract

On the basis of the transport features and experimental phenomena observed in studies of molecular motors, we propose a double-temperature ratchet model of coupled motors to reveal the dynamical mechanism of cooperative transport of motors with two heads, where the interactions and asynchrony between two motor heads are taken into account. We investigate the collective unidirectional transport of coupled system and find that the direction of motion can be reversed under certain conditions. Reverse motion can be achieved by modulating the coupling strength, coupling free length, and asymmetric coefficient of the periodic potential, which is understood in terms of the effective potential theory. The dependence of the directed current on various parameters is studied systematically. Directed transport of coupled Brownian motors can be manipulated and optimized by adjusting the pulsation period or the phase shift of the pulsation temperature.

Rotation-translation coupling of a double-headed Brownian motor in a traveling-wave potential

“…So far, great attention has been paid to coordinated transport, especially the directed transport of double-headed Brownian motors. Due to the directed motion of a double-headed Brownian motor along a periodic potential, only the translational degree of freedom has been concerned in most of works [31][32][33][34]. Recently, the development of experimental technology has brought more exciting findings.…”

A dynamical transition of a chain of charged particles in a 2D substrate potential

“…This interaction-induced transport is based on the collective behavior of interacting particles that yield a large amount of new spatiotemporal nonequilibrium. The breaking behavior related to parity and time symmetries and system nonlinearity become the new mechanisms for inducing directional transport, e.g., controlling the interaction potential by time-dependent length modulation between particles [27] and an asymmetrically coupled lattice in a symmetric potential without external force [25,28]. Inspired by how molecular motors convert chemical energy into directional motion [29,30], interest in these studies has now focused on driving energy that can be converted into directional motion in another direction.…”

The single- and double-particle properties and the current reversal of coupled Brownian motors

“…In the early studies of ratchet models, the structure of a Brownian motor, which was treated as a point particle, was completely neglected. Because the rich ratchet effects and the reversed motion of the coupled particles widely exist in many situation, such as studies of the sliding friction, the diffusion of dimers on surfaces, the diffusion of colloidal particles, and biological molecular motors [16][17][18][19][20][21][22][23][24], the dynamics of coupled Brownian particles has been the focus of concern in recent decades [25][26][27][28][29][30][31][32][33][34]. Klumpp et al studied the motion of two harmonically coupled Brownian particles in a sawtooth potential, which are subject to temporally correlated multiplicative noise.…”