arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2009.07600cond-mat.stat-mech
收藏

线性非平衡等式的平衡自由能差

Equilibrium free energy differences from a linear nonequilibrium equality

Geng Li, Z. C. Tu

摘要:

从非平衡测量中提取平衡信息是理解物理、化学和生物系统热力学性质的一项具有挑战性的任务。贾津斯基等式的发现揭示了根据非平衡驱动过程中所做的功来估计平衡自由能差的方法。然而,非线性(指数)关系导致Jarzynski等式的收敛性差。在这里,我们提出了一个简洁的方法来估计自由能差,通过一个线性非平衡等式,固有的收敛速度比非线性非平衡等式。这种线性非平衡等式依赖于一个加速的等温过程,这是通过使用统一的变分方法,命名为变分捷径等温实现。我们将我们的方法应用于欠阻尼布朗粒子在双势阱中的运动。仿真结果表明,该方法能够准确、高效地估计自由能差。特别是在高耗散的快速驱动过程中,与基于非线性非平衡等式的估计器相比,该方法可以将精度提高一个数量级以上。

英文摘要:

Extracting equilibrium information from nonequilibrium measurements is a challenge task of great importance in understanding the thermodynamic properties of physical, chemical, and biological systems. The discovery of the Jarzynski equality illumines the way to estimate the equilibrium free energy difference from the work performed in nonequilibrium driving processes. However, the nonlinear (exponential) relation causes the poor convergence of the Jarzynski equality. Here, we propose a concise method to estimate the free energy difference through a linear nonequilibrium equality which inherently converges faster than nonlinear nonequilibrium equalities. This linear nonequilibrium equality relies on an accelerated isothermal process which is realized by using a unified variational approach, named variational shortcuts to isothermality. We apply our method to an underdamped Brownian particle moving in a double-well potential. The simulations confirm that the method can be used to accurately estimate the free energy difference with high efficiency. Especially during fast driving processes with high dissipation, the method can improve the accuracy by more than an order of magnitude compared with the estimator based on the nonlinear nonequilibrium equality.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑