Thermal resonance induced by quasi-Casimir coupling for innovative nanoscale thermal management

准Casimir热传递是一种从热传导到热辐射的过渡过程中的一种新的热传递模式，它导致了两个物体之间的界面热共振。然而，纳米结构和固体表面的吸附水层之间的准Casimir耦合仍然值得商榷。因此，我们将利用非平衡分子动力学，通过纳米结构和吸附水层来验证声子在纳米隙中的传输，重点是准Casimir耦合和热共振。在2022财年，我们使用程序LAMMPS进行了分子动力学模拟。在铂与水分子吸附的纳米间隙中，不仅固体分子之间存在热共振现象，而且液体分子之间也存在声子输运现象。在非平衡状态下，通过纳米间隙的热流密度随间隙的减小呈指数增加，液体吸附层原子之间的热共振与固体界面层原子之间的热共振同时发生。此外，还阐明了碳化硅分子端基原子(Si-C、C-Si、Si-Si和C-C)对碳化硅纳米隙中的热共振现象和声子输运的影响。这些结果已在2022年热工程会议上发表，并由皇家化学学会在《物理化学-化学物理与纳米尺度》上发表。

Quasi-Casimir heat transfer, a new heat transfer mode in the transition regime from heat conduction to thermal radiation, results in the interfacial thermal resonance between two objects. However, the quasi-Casimir coupling between the nanostructures and adsorbed water layers on the solid surfaces is still open for question. Therefore, using nonequilibrium molecular dynamics, we will verify phonon transmission across a nanogap via nanostructures and adsorbed water layers, focusing on quasi-Casimir coupling and thermal resonance.In the FY 2022, we performed molecular dynamics simulation using the package program LAMMPS. In the nanogap of Pt adsorbed with water molecules, thermal resonance phenomena and phonon transport at the interface were confirmed not only between solid molecules but also between liquid molecules. In a nonequilibrium state, the heat flux across the nanogap increases exponentially with decreasing gap distance, and the thermal resonance between the atoms of the liquid adsorption layers co-occurs with the thermal resonance between the atoms of the solid interface layers. Moreover, the effects of the SiC molecular termination atoms (Si-C, C-Si, Si-Si, and C-C) on the thermal resonance phenomena and phonon transport in the SiC nanogap were clarified.These results have been presented at the 2022 Thermal Engineering Conference and published in Physical Chemistry Chemical Physics and Nanoscale by the Royal Society of Chemistry.