论文标题
来自Moiré-Hofstadter Phonon的分形非Fermi液体
Fractal non-Fermi liquids from moiré-Hofstadter phonons
论文作者
论文摘要
从理论上讲，我们探索了晶格 - 均匀磁场中的2DMoiré异质结构，作为非fermi液体物理学范式模型的量子模拟的平台：Fermi-Surplace-Surplace耦合与波动量规场的耦合。在这些Moiré-Hofstadter（MH）系统中，长波长声音子与类似于具有2D量规场的电子类似的电子表现出奇异的相互作用。这导致低温下费米 - 液体理论的分解。我们表明，与散装晶体相比，大型的Moiré-Unit细胞大小，可调的费米表面拓扑结合，增强的耦合与层间滑动模式的耦合增强了这些效果，从而使许多型级别的效果都在实验覆盖范围内增强。尽管我们发现渐近的低温非FERMI液体状态仍然存在于低温下，但可以观察到引人注目的前体非Fermi液体特征，我们提出表面声波衰减和量子振荡运输实验。我们还研究了MH原声 - 纯龙的运动，我们预测，对数有效质量和非常规的磁场缩放表现出对数的分化，以缩放回旋子共振频率和量子振荡振幅。
We theoretically explore 2d moiré heterostructures in lattice-commensurate magnetic fields as platforms for quantum simulation of a paradigmatic model of non-Fermi liquid physics: a Fermi-surface coupled to a fluctuating gauge field. In these moiré-Hofstadter (MH) systems, long-wavelength acoustic phonons exhibit singular interactions with electrons analogous to those of electrons with 2d gauge fields. This leads to a breakdown of Fermi-liquid theory at low temperatures. We show that a combination of large moiré-unit cell size, tunable Fermi-surface topology, and enhanced coupling to interlayer sliding modes, enhance these effects by over many orders-of-magnitude compared to bulk crystals, placing them within experimental reach. Though we find that the asymptotic low-temperature non-Fermi liquid regime remains at prohibitively low temperatures, striking precursor non-Fermi liquid signatures can be observed, and we propose surface acoustic wave attenuation and quantum oscillation transport experiments. We also study the motion of MH acoustic-polarons, which we predict exhibit logarithmically diverging effective mass and unconventional magnetic field scaling for scaling of cyclotron resonance frequency and quantum oscillation amplitude.
