To what extent the orientational order of self-propelling particles affects the dynamics of active bath-immersed ratchet devices remains unclear. We report experimental results of an inverse $\lambda$-like transition of the angular velocity of two ratchet gears in an active bath of self-propelling granular rods (SPRs) at different gear distances. The transition is caused by the phase transition in the orientational order of those SPRs located in the space between the gears. Brownian dynamics simulation of confined SPRs supports these observations. Thus, conditions for the upper bound efficiency of systems of active ratchet gears were obtained.

中文翻译：

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主动浴中棘轮动力学中的类λ过渡

尚不清楚自推进粒子的取向顺序在多大程度上影响有源浴浸式棘轮装置的动力学。我们报告逆实验结果$\lambda$在不同齿轮距离下的自驱动颗粒杆（SPR）的主动浴中，两个棘轮齿轮的角速度的变化类似。过渡是由位于齿轮之间空间中那些SPR的定向顺序的相变引起的。受限SPR的布朗动力学模拟支持了这些观察结果。因此，获得了主动棘轮齿轮系统的上限效率的条件。