标题： 从近场到极端近场辐射传热的转变 显示英文标题

标题： Transition from near-field to extreme near-field radiative heat transfer

摘要： 极端近场范围内的辐射热传导，即距离小于10纳米时的情况，仍然没有被很好地理解。在这个范围内存在相互矛盾的实验结果，其中一些与理论预测非常吻合，而另一些则报告了显著增强的热流，比理论所建议的大几个数量级。非平衡涨落电动力学理论是否能够预测这种极端近场范围内的辐射热传导仍然是一个活跃争论的问题。 在这项研究中，在接近接触前的近场和极端近场过渡区域之间，展示了一个镀金球体与镀金薄膜样品之间的辐射热传导测量。通过使用配备有尖端温度传感器作为热流传感器的近场扫描热显微镜来进行辐射热流测量。 我们发现在近场范围内，与非平衡涨落电动力学的理论预测有很好的一致性。然而，在极端近场范围内，观察到的辐射热流值大约比理论预测高出100倍，这表明非平衡涨落电动力学无法捕捉该范围内的辐射热流。 显示英文摘要

摘要： The radiative heat transfer in the extreme near-field regime, i.e. for distances below 10 nm, remains poorly understood. There are competing experimental results in this regime, with some in good agreement with theoretical predictions, while others report drastically elevated heat fluxes, orders of magnitude larger than what theory suggests. Whether the theory of fluctuational electrodynamics can predict the radiative heat transfer in this extreme near-field regime or not remains a matter of active debate. In this study, a radiative heat transfer measurement is presented between a gold-coated sphere and a gold film sample in the transition regime between the near-field and the extreme near-field regime just before contact. The radiative heat flux measurement is made by using a near-field scanning thermal microscope equipped with a temperature sensor at a sharp tip as a heat flux sensor. We find an excellent agreement with the theoretical predictions of fluctuational electrodynamics in the near-field regime. In the extreme near-field regime however, a highly increased radiative heat flux is observed with values about 100 times larger than the theoretical predictions, indicating that fluctuational electrodynamics fails to capture the radiative heat flux in this regime.