论文标题
跨纳米间隙的热传输：声子传输与空气传导
Thermal transport across nanometre gaps: phonon transmission vs air conduction
论文作者
论文摘要
通过纳米间隙隔开的两个表面之间的传热对于从间距磁盘系统，扫描热显微镜和气凝胶中热传输的许多应用都很重要。在这些分离距离上，近场辐射传热与声子介导的传热竞争。 在这里，我们使用晶格动力学与AB-Initio计算相结合，量化了声子辅助热传递的贡献。我们清楚地证明了声子在亚纳米级间隙中主导了传热。令人惊讶的是，我们得出的结论是，即使在缝隙填充空气分子的情况下，声子也能在几乎接触的两个固体之间提供主要的能通道。我们的结果可以预测，与以前的作品相比，声子传热的数量级增强了，并提出了一种方法，可以分析跨纳米级真空间隙之间的声子传播。
Heat transfer between two surfaces separated by a nanometre gap is important for a number of applications ranging from spaced head disk systems, scanning thermal microscopy and thermal transport in aerogels. At these separation distances, near field radiative heat transfer competes with heat transfer mediated by phonons. Here we quantify the contribution of phonon assisted heat transfer between apolar solids using lattice dynamics combined with ab-initio calculations. We clearly demonstrate that phonons dominate heat transfer for subnanometre gaps. Strikingly, we conclude that even in the situation where the gap is filled with air molecules, phonons provide the dominant energy channel between the two solids nearly in contact. Our results predict orders of magnitude enhanced phonon heat transfer compared to previous works and bring forward a methodology to analyse phonon transmission across nanoscale vacuum gaps between apolar materials.
