Hu Hai-Wei, Du Lin, Fan Ai-Li, Deng Zi-Chen, Grebogi Celso
School of Mathematics and Statistics, Northwestern Polytechnical University, Xi'an 710072, China.
MIIT Key Laboratory of Dynamics and Control of Complex Systems, Northwestern Polytechnical University, Xi'an 710072, China.
Phys Rev E. 2024 May;109(5-1):054110. doi: 10.1103/PhysRevE.109.054110.
We demonstrate the existence of entropic stochastic resonance (ESR) of passive Brownian particles with finite size in a double- or triple-circular confined cavity, and compare the similarities and differences of ESR in the double-circular cavity and triple-circular cavity. When the diffusion of Brownian particles is constrained to the double- or triple-circular cavity, the presence of irregular boundaries leads to entropic barriers. The interplay between the entropic barriers, a periodic input signal, the gravity of particles, and intrinsic thermal noise may give rise to a peak in the spectral amplification factor and therefore to the appearance of the ESR phenomenon. It is shown that ESR can occur in both a double-circular cavity and a triple-circular cavity, and by adjusting some parameters of the system, the response of the system can be optimized. The differences are that the spectral amplification factor in a triple-circular cavity is significantly larger than that in a double-circular cavity, and compared with the ESR in a double-circular cavity, the ESR effect in a triple-circular cavity occurs within a wider range of external force parameters. In addition, the strength of ESR also depends on the particle radius, and smaller particles can induce more obvious ESR, indicating that the size effect cannot be safely neglected. The ESR phenomenon usually occurs in small-scale systems where confinement and noise play an important role. Therefore, the mechanism that is found could be used to manipulate and control nanodevices and biomolecules.
我们证明了在双圆或三圆受限腔中具有有限尺寸的被动布朗粒子存在熵随机共振（ESR），并比较了双圆腔和三圆腔中ESR的异同。当布朗粒子的扩散被限制在双圆或三圆腔内时，不规则边界的存在会导致熵垒。熵垒、周期性输入信号、粒子的重力和固有热噪声之间的相互作用可能会导致频谱放大因子出现峰值，从而出现ESR现象。结果表明，ESR可以在双圆腔和三圆腔中发生，通过调整系统的一些参数，可以优化系统的响应。不同之处在于，三圆腔中的频谱放大因子明显大于双圆腔中的频谱放大因子，并且与双圆腔中的ESR相比，三圆腔中的ESR效应在更宽的外力参数范围内出现。此外，ESR的强度还取决于粒子半径，较小的粒子可以诱导更明显的ESR，这表明尺寸效应不能被忽视。ESR现象通常发生在限制和噪声起重要作用的小规模系统中。因此，所发现的机制可用于操纵和控制纳米器件和生物分子。
