研究了在强垂直磁场作用下二维电子系统的量子霍尔效应。在大的间隔（d）极限下，延迟效应是必不可少的，我们发现：i）卡西米尔力以3 \hbar c α^2/（8π^2 d^4）为单位量子化; ii）对于具有相同类型载流子的反射镜，卡西米尔力是排斥力，而对于具有相反类型载流子的反射镜，卡西米尔力是吸引力。因此，卡西米尔力的符号在双极材料如石墨烯中是电可调的。当一个反射镜是处于填充因子ν=0量子霍尔态的电荷中性石墨烯系统时，卡西米尔力被抑制。
英文摘要：
We investigate the Casimir effect between two-dimensional electron systems driven to the quantum Hall regime by a strong perpendicular magnetic field. In the large separation (d) limit where retardation effects are essential we find i) that the Casimir force is quantized in units of 3\hbar c α^2/(8π^2 d^4), and ii) that the force is repulsive for mirrors with same type of carrier, and attractive for mirrors with opposite types of carrier. The sign of the Casimir force is therefore electrically tunable in ambipolar materials like graphene. The Casimir force is suppressed when one mirror is a charge-neutral graphene system in a filling factor ν=0 quantum Hall state.
In a recent paper (arXiv:2003.00760) and a related article (Z. Naturforsch. A 75, 803-807), S.-A. Biehs et al. present erroneous interpretations of our work on the heat transfer driven by Casimir force. Here, we clarify several key concepts and refute their claims.
The Casimir force and thermal Casimir force originating from quantum electromagnetic fluctuations at zero and non-zero temperatures, respectively, are significant in nano- and microscale systems and are well-understood. Less understood, however, are the Casimir and thermal Casimir forces in systems breaking Lorentz reciprocity. In this work, we derive a formalism for thermal Casimir forces between an arbitrary number of spheres based on fluctuational electrodynamics and scattering theory without the assumption of Lorentz reciprocity. We study the total Casimir force in systems of two and three…
Thermal Casimir Force Imaging of Nonequilibrium Hot Electrons
Fudan University（复旦大学）；ShanghaiTech University（上海科技大学）；Carl von Ossietzky Universität（卡尔·冯·奥西茨基大学）；Shanghai Institute of Technical Physics, Chinese Academy of Sciences（中国科学院技术物理研究所）；Hefei National Laboratory（合肥国家实验室）
