Exact scattering cross section for lattice-defect scattering of phonons

arXiv - PHYS - Computational Physics Pub Date : 2024-08-30 DOI:arxiv-2408.17004

Zhun-Yong Ong

{"title":"Exact scattering cross section for lattice-defect scattering of phonons","authors":"Zhun-Yong Ong","doi":"arxiv-2408.17004","DOIUrl":null,"url":null,"abstract":"The use of structurally complex lattice defects, such as functional groups,\nembedded nanoparticles, and nanopillars, to generate phonon scattering is a\npopular approach in phonon engineering for thermoelectric applications.\nHowever, the theoretical treatment of this scattering phenomenon remains a\nformidable challenge, especially with regards to the determination of the\nscattering cross sections and rates associated with such lattice defects. Using\nthe extended Atomistic Green's Function (AGF) method, we describe how the\nnumerically exact mode-resolved scattering cross section \\sigma can be computed\nfor a phonon scattered by a single lattice defect. We illustrate the generality\nand utility of the AGF-based treatment with two examples. In the first example,\nwe treat the isotopic scattering of phonons in a harmonic chain of atoms . In\nthe second example, we treat the more complex problem of phonon scattering in a\ncarbon nanotube (CNT) containing an encapsulated C60 molecule which acts as a\nscatterer of the CNT phonons. The application of this method can enable a more\nprecise characterization of lattice-defect scattering and result in the more\ncontrolled use of nanostructuring and lattice defects in phonon engineering for\nthermoelectric applications.","PeriodicalId":501369,"journal":{"name":"arXiv - PHYS - Computational Physics","volume":"172 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Computational Physics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2408.17004","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}

引用次数: 0

Abstract

The use of structurally complex lattice defects, such as functional groups, embedded nanoparticles, and nanopillars, to generate phonon scattering is a popular approach in phonon engineering for thermoelectric applications. However, the theoretical treatment of this scattering phenomenon remains a formidable challenge, especially with regards to the determination of the scattering cross sections and rates associated with such lattice defects. Using the extended Atomistic Green's Function (AGF) method, we describe how the numerically exact mode-resolved scattering cross section \sigma can be computed for a phonon scattered by a single lattice defect. We illustrate the generality and utility of the AGF-based treatment with two examples. In the first example, we treat the isotopic scattering of phonons in a harmonic chain of atoms . In the second example, we treat the more complex problem of phonon scattering in a carbon nanotube (CNT) containing an encapsulated C60 molecule which acts as a scatterer of the CNT phonons. The application of this method can enable a more precise characterization of lattice-defect scattering and result in the more controlled use of nanostructuring and lattice defects in phonon engineering for thermoelectric applications.

查看原文本刊更多论文

声子晶格缺陷散射的精确散射截面

利用结构复杂的晶格缺陷（如功能基团、嵌入式纳米粒子和纳米柱）产生声子散射是热电应用声子工程中的一种流行方法。然而，这种散射现象的理论处理仍然是一项艰巨的挑战，尤其是在确定与这种晶格缺陷相关的散射截面和速率方面。利用扩展的原子格林函数（AGF）方法，我们描述了如何计算单个晶格缺陷散射声子的精确模态分辨散射截面（sigma）。我们用两个例子来说明基于 AGF 的处理方法的通用性和实用性。在第一个例子中，我们处理了声子在原子谐波链中的同位素散射。在第二个例子中，我们处理了更为复杂的碳纳米管（CNT）中的声子散射问题，碳纳米管中含有一个封装的 C60 分子，它是碳纳米管声子的散射体。应用这种方法可以更精确地描述晶格缺陷散射，从而在热电应用的声子工程中更有控制地使用纳米结构和晶格缺陷。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

arXiv - PHYS - Computational Physics

自引率

0.00%

发文量