Lee Dong Yun, Um Jaegon, Paneru Govind, Pak Hyuk Kyu
Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan, 44919, Republic of Korea.
CCSS, CTP and Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea.
Sci Rep. 2018 Aug 14;8(1):12121. doi: 10.1038/s41598-018-30495-6.
We present an experimental realization of an information-driven Brownian motor by periodically cooling a Brownian particle trapped in a harmonic potential connected to a single heat bath, where cooling is carried out by the information process consisting of measurement and feedback control. We show that the random motion of the particle is rectified by symmetry-broken feedback cooling where the particle is cooled only when it resides on the specific side of the potential center at the instant of measurement. Studying how the motor thermodynamics depends on cycle period τ relative to the relaxation time τ of the Brownian particle, we find that the ratcheting of thermal noise produces the maximum work extraction when τ ≥ 5τ, while the extracted power is maximum near τ = τ, implying the optimal operating time for the ratcheting process. In addition, we find that the average transport velocity is monotonically decreased as τ increases and present the upper bound for the velocity.
我们展示了一种信息驱动布朗马达的实验实现方式，通过周期性地冷却被困在与单个热库相连的谐振势中的布朗粒子来实现，其中冷却是由包含测量和反馈控制的信息过程来执行的。我们表明，粒子的随机运动通过对称破缺反馈冷却得以整流，即仅当粒子在测量瞬间位于势中心的特定一侧时才对其进行冷却。研究马达热力学如何依赖于相对于布朗粒子弛豫时间τ的循环周期τ，我们发现当τ≥5τ时，热噪声的棘轮效应产生最大的功提取，而提取功率在τ = τ附近最大，这意味着棘轮过程的最佳运行时间。此外，我们发现平均传输速度随着τ的增加而单调降低，并给出了速度的上限。
