[论文解读] Atomic binding, geometric monolayer tiny particle, atomic deformation and one-dimensional stretching

Mubarak Ali|arXiv (Cornell University)|Sep 26, 2016

Laser-Ablation Synthesis of Nanoparticles被引用 11

一句话总结

该论文提出，电子跃迁和光子耦合驱动非平衡系统中的原子结合，形成几何单层微小颗粒——特别是菱形金簇——作为基本构建单元。通过电子束的一维拉伸可改变其几何结构与电子结构，揭示了通过弹性电子态动力学实现各向异性颗粒组装的机制。

ABSTRACT

In many materials, the formation of building blocks and their controlled angle packing under horizontal drive result into various anisotropic geometric shapes/large-sized particles. These trends become more pronounced in materials having elements of higher atomic number which supports our view that binding of atoms in non-equilibrium systems takes place by means of electronic transitions/photon couplings. In processing various colloidal solutions, dynamics manipulates the geometry of tiny particles as well as their packing into large sized particles at air-solution/planar interface. Monolayer tiny particle geometry like rhombus shape is vital as it forms the building block of all anisotropic geometric shapes. At plasma-solution interface, impinging electron streams at a certain angle to such tiny particle stretch it one-dimensionally and reduce its altitude, thus, it packs under directional interaction and all of the published studies appear to deal with such building block in the formation of various anisotropic geometric shapes. In this work, I suggest that elastically driven electronic states of atoms provide the fundamental process for formation of this building block. To demonstrate the process, a building block of gold atoms is taken as a model system. On get-together of atoms per unit area they configure into geometric monolayer tiny particle under their attained dynamics and where photon couplings provide the binding force between them. Study further throws light on one-dimensional stretching of such tiny particle and role of higher energy photons in modifying its electronic structure into smooth elements along with atomic deformation. The study encompasses diversified areas of condensed-matter physics and highlights several unaddressed issues.

研究动机与目标

• 研究电子跃迁与光子耦合在非平衡系统中原子结合中的作用。
• 理解单层微小颗粒（特别是菱形金簇）作为各向异性几何形状构建单元的形成机制。
• 探讨定向电子束撞击对一维拉伸与原子形变的影响。
• 阐明高能光子在调节电子结构并实现平滑结构转变中的作用。

提出的方法

• 将金原子作为代表性体系，模拟动态条件下原子堆积行为。
• 通过界面处的电子跃迁机制与光子耦合分析原子结合。
• 利用特定角度的定向电子束流模拟单层颗粒的一维拉伸。
• 通过等离子体-溶液或气相-溶液界面处的动态相互作用，研究几何演化与电子结构变化。
• 以弹性电子态动力学作为结构重构的核心机制。
• 将胶体加工中的实验趋势整合进粒子各向异性理论框架。

实验结果

研究问题

• RQ1 电子跃迁与光子耦合如何促进非平衡系统中原子结合？
• RQ2 单层微小颗粒（特别是菱形簇）在形成各向异性几何形状中起什么作用？
• RQ3 定向电子束撞击如何诱导一维拉伸并降低颗粒高度？
• RQ4 高能光子以何种方式改变电子结构并促进微小颗粒中结构的平滑性？
• RQ5 在动态条件下，原子聚集形成构建单元的潜在机制是什么？

主要发现

• 单层微小颗粒，特别是菱形金簇，作为各向异性颗粒形成的 fundamental building blocks 出现。
• 光子耦合是动态组装的单层颗粒中原子间主要结合力。
• 特定角度的定向电子束可诱导一维拉伸，降低颗粒高度，实现定向排列。
• 弹性电子态动力学是这些构建单元形成与重构的内在机制。
• 高能光子可调节电子结构，促进颗粒中更平滑的结构元素形成。
• 本研究识别出凝聚态物理中关于原子级几何控制与电子跃迁尚未解决的问题。