电场对粗糙介电表面附近电解质的影响：基于GPU加速代码的研究
Electric field effects on electrolytes near rough dielectric surfaces by GPU-accelerated code
浏览论文内容
中文总结 AI 辅助
本研究通过分子动力学和解析计算，揭示了电场可调控粗糙介电表面附近的离子分布，并开发了GPU加速的LAMMPS DIELECTRIC包，实现2.4-24倍提速及电场模拟能力。
中文摘要 AI 辅助
介电界面在制造和自然系统中无处不在，例如离子电子器件、超级电容器和活细胞。这些通常粗糙的介电表面承载着依赖于表面几何形状和存在电场的离子电荷分布。在本工作中，我们研究了电场对这类离子电荷分布的影响。通过分子动力学（MD）和微扰解析计算，我们证明了由正弦界面产生的交替离子电荷密度区域模式可以通过施加电场来改变和反转。我们确定了抵消介电界面驱动的离子密度调制效应所需的临界电场强度，并为表面高度小振幅正弦变化的情况开发了该电场的解析表达式。我们表明，对于由傅里叶模式之和给出的表面高度，其附近的离子浓度可以通过将每种模式引起的浓度调制的贡献相加来获得，从而使得预测粗糙表面附近的离子分布成为可能。我们更新并验证了一个用于极化表面MD模拟的LAMMPS包，即DIELECTRIC包，通过实现一个新版本，在我们的测试系统上通过GPU并行化实现了2.4至24倍的速度提升，并增加了在任意粗糙度的介电界面附近对简单和复杂电解质模拟施加电场的能力。
英文摘要
Dielectric interfaces are ubiquitous in manufactured and natural systems, such as iontronic devices, supercapacitors, and living cells. These, often rough, dielectric surfaces host ionic charge distributions that depend on the surface geometry and the electric fields present. In this work, we study the effect of electric fields on such ionic charge distributions. We demonstrate, by molecular dynamics (MD) and perturbative analytic calculations, that the pattern of alternating regions of ionic charge density created by a sinusoidal interface can be modified and reversed by applying an electric field. We determine the strength of the critical electric field required to cancel the effect of dielectric interface-driven modulation in ion density and develop an analytic expression for that field for small amplitude sinusoidal variations in surface height. We show that ion concentrations near a surface with height given by a sum of Fourier modes can be found by adding the contributions from the concentration modulation due to each mode, allowing the possibility to predict ion distributions near rough surfaces. We updated and validated a LAMMPS package for MD simulation of polarizable surfaces, the DIELECTRIC package, by implementing a new version that achieves a 2.4-24 times speed increase by GPU parallelization on our test system and adds the capability to simulate an applied electric field on simple and complex electrolytes near dielectric interfaces with arbitrary roughness.
