Demonstration of an Unusual Thermal Effect in the Casimir Force from Graphene
Demonstration of an Unusual Thermal Effect in the Casimir Force from Graphene
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DOI：
10.1103/physrevlett.126.206802
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发表时间：
2021-05-20
影响因子：
8.6
通讯作者：
Mohideen, U.
中科院分区：
文献类型：
--
作者：
Liu, M.;Zhang, Y.;Mohideen, U.
我们报道了对镀金球体和沉积在石英板上的石墨烯之间Casimir力梯度的精确测量。用Dirac模型框架中的极化张量将测量数据与精确的理论进行了比较，该模型考虑了石墨烯样品的非零化学势和能隙的影响，但没有合适的参数。实验和理论的很好的一致性表明，在1微米以下的间隔处有异常大的热效应，这在传统的三维材料中是从未观察到的。从而从实验上证实了石墨烯的有效温度是由费米速度而不是光速决定的。
We report precision measurements of the gradient of the Casimir force between an Au-coated sphere and graphene sheet deposited on a silica plate. The measurement data are compared with exact theory using the polarization tensor found in the framework of the Dirac model including effects of the nonzero chemical potential and energy gap of the graphene sample with no fitting parameters. The very good agreement between experiment and theory demonstrates the unusually big thermal effect at separations below 1 mu m which has never been observed for conventional 3D materials. Thus, it is confirmed experimentally that for graphene the effective temperature is determined by the Fermi velocity rather than by the speed of light.