发表机构
Hong Kong University of Science and Technology; Massachusetts Institute of Technology（香港科技大学; 麻省理工学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究发现传统弗里德尔振荡理论在布洛赫波函数有非平凡量子几何时不完整。在含孤立费米能平带金属中，量子几何引发独特振荡即量子几何弗里德尔振荡，其周期由平带量子度规热点动量空间间距决定，且在高温下也能持续。
AI 中文摘要
在传统弗里德尔振荡中，杂质诱导的实空间电荷密度振荡由费米动量设定振荡周期。本文表明，当布洛赫波函数携带非平凡量子几何时，传统理论不完整。我们证明，在费米能处有孤立（近）平带的金属中，量子几何会引发一种独特的振荡，我们称之为“量子几何弗里德尔振荡”（QGFOs）。QGFOs的周期由平带量子度规热点的动量空间分离设定。传统振荡和量子度规诱导的振荡在低温下共存。在较高温度下，远离杂质位点的传统弗里德尔振荡由热长度设定，因此振荡很容易被温度效应冲刷掉。值得注意的是，QGFOs的衰减长度由量子度规长度设定，该长度由平带量子度规的积分定义。结果，即使在温度远高于平带带宽时，QGFOs也能持续。此外，在很宽的温度范围内，衰减长度与温度无关，这是量子度规保护的一种表现。总之，我们表明量子度规会引发新的弗里德尔振荡。我们的工作表明，测量QGFOs是检测量子度规长度（与量子度规积分相关）和量子度规热点间距（与动量空间中量子度规分布相关）的有力方法。
英文摘要
In conventional Friedel oscillations, the real-space charge density oscillations induced by an impurity are characterized by an oscillation period set by the Fermi momentum. In this work, we demonstrate that in metals with an isolated (nearly) flat band at the Fermi energy, quantum geometry induces a distinct type of oscillations, which we call the \emph{quantum geometric Friedel oscillations} (QGFOs). The period of the QGFOs is set by the momentum-space separation of the quantum metric hot spots of the isolated band. The conventional and quantum metric-induced oscillations can coexist at low temperatures. At higher temperatures, the conventional Friedel oscillation amplitudes away from the impurity site are set by the thermal length such that the oscillations can be easily washed out by temperature effects. Remarkably, the QGFOs decay length is set by the quantum metric length which is defined by the integration of the quantum metric of the isolated band. As a result, the QGFOs can persist even at temperatures much larger than the bandwidth of the isolated flat band. Moreover, the decay length is invariant for a wide range of temperature which is a striking result. In conclusion, we show that the quantum metric induces novel Friedel oscillations. Our work suggests that the measurement of the QGFOs is a powerful way to detect the quantum metric length (which is associated with the integral of the quantum metric) and the quantum metric hot spot separations (which are associated with the distribution of the quantum metric in the momentum space).
