发表机构
Hebei University; South China Normal University（河北大学; 华南师范大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
实验实现尘埃等离子体摇摆棘轮，发现电流反转，提出基于驱动力与棘轮约束竞争的模型，定量解释输运区域。
AI 中文摘要
单个尘埃颗粒被限制在非对称棘轮势中，由两束方向相反的激光束周期性地驱动，形成欠阻尼尘埃等离子体摇摆棘轮。我们实验研究了颗粒在不同驱动幅度和频率下的输运动力学。根据驱动条件，颗粒表现出正向、零或负向净电流，并且当驱动参数跨越临界阈值时观察到电流反转。为了解释这些输运行为，我们建立了一个基于驱动力与棘轮约束之间竞争的简化模型。该模型揭示了定向输运由两个条件决定：驱动力必须超过去钉扎阈值，并且驱动半周期的持续时间必须长于从棘轮势阱中爬升逃逸的时间。由此得到的动态相图定量地再现了实验观察到的输运区域和电流反转。这些结果表明，尘埃等离子体是研究摇摆棘轮中欠阻尼颗粒非平衡输运现象的多功能平台。
英文摘要
A single dust particle confined in an asymmetric ratchet potential is periodically driven by two oppositely directed laser beams, forming an underdamped dusty plasma rocking ratchet. We experimentally investigate the transport dynamics of the particle under varying driving amplitudes and frequencies. Depending on the driving conditions, the particle exhibits positive, zero, or negative net currents, and current reversal is observed when the driving parameters cross critical thresholds. To interpret these transport behaviors, we develop a simplified model based on the competition between the driving force and the ratchet confinement. The model reveals that directional transport is governed by two requirements: the driving force must exceed the depinning threshold, and the duration of a driving semicycle must be longer than the uphill escape time from a ratchet well. The resulting dynamic phase diagram quantitatively reproduces the experimentally observed transport regimes and current reversals. These results demonstrate dusty plasma as a versatile platform for investigating nonequilibrium transport phenomena of underdamped particles in rocking ratchets.
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