标题： 轴子暗物质与量子霍尔效应中的平台-平台转变 显示英文标题

标题： Axion Dark Matter and Plateau-Plateau Transition in Quantum Hall Effect

摘要： 轴子暗物质在使用强磁场的量子霍尔效应实验中不可避免地产生电磁辐射。尽管这些辐射非常微弱，但我们通过一个QCD轴子模型表明，它们在低温（低于$100$ mK）下影响二维电子大表面积（大于$10^{-3}\rm cm^2$）系统的平台-平台转换。通过分析之前显示过渡宽度$\Delta B$随温度和微波频率变化而饱和的实验，我们提供了轴子存在的证据。值得注意的是，在大多数没有轴子效应的实验中，饱和频率$f_s(T)$在温度为$100$ mK或更高以及系统尺寸为$10^{-3}\rm cm^2$或更小时小于$1$ GHz。 此外，频率$f_s(T)$随温度降低或系统尺寸增大而减小。 然而，有一些实验显示，在低温 35 mK 和较大的霍尔条表面面积$6.6\times 10^{-3}\rm cm^2$的情况下，饱和频率为$f_s(T)\simeq 2.4$GHz。 大约$2.4$GHz 的相同频率也在不同的平台转换和不同尺寸的霍尔条中被观察到。 这些意外的结果是由轴子微波引起的。 饱和频率$f_s=m_a/2\pi$为$\simeq 2.4$GHz 表明轴子质量为$\simeq 10^{-5}$eV。 通过将轴子效应与宽度上的热效应进行比较$\Delta B$，我们证明了在低于$50$mK 的低温下，轴子效应比热效应占主导地位。轴子效应的主导性归因于轴子能量的显著吸收，该吸收与参与电子数的平方成正比。 显示英文摘要

摘要： Axion dark matter inevitably generates electromagnetic radiation in quantum Hall effect experiments that use strong magnetic fields. Although these emissions are very weak, we have shown using a QCD axion model that they influence the plateau-plateau transition at low temperatures (below $100$ mK) in a system with a large surface area (greater than $10^{-3}\rm cm^2$) of two-dimensional electrons. By analyzing previous experiments that show saturation of the transition width $\Delta B$ as temperature and microwave frequency change, we provide evidence for the presence of axions. Notably, in most experiments without axion effects, the saturation frequency $f_s(T)$ is less than $1$ GHz at temperatures of $100$ mK or higher and for system sizes of $10^{-3}\rm cm^2$ or smaller. Additionally, the frequency $f_s(T)$ decreases with decreasing temperature or increasing system size. However, there are experiments that show a saturation frequency $f_s(T)\simeq 2.4$GHz despite a low temperature of 35 mK and a large surface area of $6.6\times 10^{-3}\rm cm^2$ for the Hall bar. This identical frequency of approximately $2.4$ GHz has also been observed in different plateau transitions and in Hall bars of varying sizes. These unexpected results are caused by axion microwaves. The saturation frequency $f_s=m_a/2\pi$ of $\simeq 2.4$ GHz implies an axion mass of $\simeq 10^{-5}$eV. By comparing the axion effect with thermal effect on the width $\Delta B$, we have shown the dominance of the axion effect over thermal effect at low temperature less than $50$mK. The dominance of the axion effect is attributed to significant absorption of axion energy, which is proportional to the square of the number of electrons involved.