Transport performance of a dimer in inertial frictional ratchets

Abstract This investigation focuses on the under-damped Brownian transport of a dimer characterized by two harmonically interacting components. The friction coefficients between the dimer components are different; thus the dynamic symmetry of the system is broken. In addition, the inertial ratchets are synchronously modulated by the feedback control protocol in time. Here, we analyze the transport performance by studying the average velocity and energy conversion efficiency of the dimer induced by friction symmetry breaking and external forces. Furthermore, we can also identify the enhancement of the centre-of-mass mean velocity and energy conversion efficiency of inertial frictional ratchets for intermediate values of the driving amplitude, coupling strength and damping force. Remarkably, in the weak bias case, the directed transport of inertial Brownian particles can be reversed twice by modulating the suitable friction of the dimer. In particular, the frictional ratchets can acquire a series of resonant steps under the influence of harmonic force. These conclusions of reliable transport in noisy environments are expected to provide insights into the performance of natural molecular motors.