...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physical review >Thermal conductivity of Si nanostructures containing defects: Methodology, isotope effects, and phonon trapping
【24h】

Thermal conductivity of Si nanostructures containing defects: Methodology, isotope effects, and phonon trapping

机译：包含缺陷的Si纳米结构的热导率：方法，同位素效应和声子俘获

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A first-principles method to calculate the thermal conductivity in nanostructures that may contain defects or impurities is described in detail. The method mimics the so-called "laser-flash" technique to measure thermal conductivities. It starts with first-principles density-functional theory and involves the preparation of various regions of a supercell at slightly different temperatures. The temperature fluctuations are minimized without using a thermostat and, after averaging over random initial conditions, temperature changes as small as 5 K can be monitored (from 120 to 125 K). The changes to the phonon density of states and the specific heat induced by several atomic percent of impurities are discussed. The thermal conductivity of Si supercells is calculated as a function of the temperature and of the impurity content. For most impurities, the drop in thermal conductivity is unremarkable. However, there exist narrow ranges of impurity parameters (mass, bond strength, etc.) for which substantial drops in the thermal conductivity are predicted. These drops are isotope dependent and appear to be related to the vibrational lifetime of specific impurity-related modes.
机译：详细介绍了计算可能包含缺陷或杂质的纳米结构中热导率的第一原理方法。该方法模仿了所谓的“激光闪光”技术来测量热导率。它从第一原理密度泛函理论开始，涉及在稍微不同的温度下制备超级电池的各个区域。在不使用恒温器的情况下，将温度波动降到最低，并且在随机初始条件下求平均值后，可以监视小至5 K（从120到125 K）的温度变化。讨论了由几个原子百分比的杂质引起的声子密度和比热的变化。根据温度和杂质含量计算出硅超级电池的热导率。对于大多数杂质，热导率的下降并不明显。但是，杂质参数（质量，粘结强度等）的范围很窄，可以预测其导热系数会大大下降。这些液滴与同位素有关，并且似乎与特定杂质相关模式的振动寿命有关。

著录项

  • 来源
    《Physical review》 |2011年第3期|p.035317.1-035317.10|共10页
  • 作者

    T. M. Gibbons; By. Kang; S. K. Estreicher; C. Carbogno;

  • 作者单位

    Physics Department, Texas Tech University, Lubbock, Texas 79409-1051, USA;

    Physics Department, Texas Tech University, Lubbock, Texas 79409-1051, USA;

    Physics Department, Texas Tech University, Lubbock, Texas 79409-1051, USA;

    Fritz-Haber-Institut der Max-Planck Gesellschaft, Faradayweg 4-6, D-14195 Berlin-Dahlem, Germany;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号