论文标题
晶体表面上的无摩擦纳米吉尼
Frictionless nanohighways on crystalline surfaces
论文作者
论文摘要
由定期原子排列统治的纳米尺度的摩擦的理解令人惊讶地不完整。在这里，我们通过研究具有任意晶格对称性的两个无限接触表面的互锁势能，并将其扩展到有限的触点，从而提供了统一的理解。我们纯粹基于几何特征，将所有可能的接触分为三种不同类型：在结构润滑的接触中，单层可以在无摩擦的情况下移动各向同性，一个波纹和强烈的互锁接触，以及新发现的方向上的结构上润滑的方向性润滑接触，该图层可以沿着一个特定的方向和其他有限的方向毫无用处地移动摩擦，并沿着其他有限的方向进行摩擦。这种新型类别在旋转扰动上具有稳定的稳定，并提供了极端的摩擦各向异性。有限尺寸的分析表明，我们的分类适用于接触的各种技术相关材料，从晶体表面上的吸附物到分层的二维材料和胶体单层。
The understanding of friction at nano-scales, ruled by the regular arrangement of atoms, is surprisingly incomplete. Here we provide a unified understanding by studying the interlocking potential energy of two infinite contacting surfaces with arbitrary lattice symmetries, and extending it to finite contacts. We categorize, based purely on geometrical features, all possible contacts into three different types: a structurally lubric contact where the monolayer can move isotropically without friction, a corrugated and strongly interlocked contact, and a newly discovered directionally structurally lubric contact where the layer can move frictionlessly along one specific direction and retains finite friction along all other directions. This novel category is energetically stable against rotational perturbations and provides extreme friction anisotropy. The finite-size analysis shows that our categorization applies to a wide range of technologically relevant materials in contact, from adsorbates on crystal surfaces to layered two-dimensional materials and colloidal monolayers.
