无限层镍酸盐中无赝隙的类边缘费米液体行为
Marginal-Fermi-Liquid-like Behavior without Pseudogap in Infinite-Layer Nickelates
浏览论文内容
中文总结 AI 辅助
研究无限层镍酸盐中赝隙、奇异金属行为和超导性的关系，利用角分辨光电子能谱解析低能谱函数，发现动量选择性关联和类边缘费米液体散射可在无类铜酸盐赝隙时发生，为高温超导正常态电子成分研究提供基准。
中文摘要 AI 辅助
在空穴掺杂的铜酸盐中，赝隙形成、奇异金属行为和非常规超导紧密相连，但其关系仍未解决。无限层镍酸盐提供了一个独特的3d9衍生平台。本文利用角分辨光电子能谱解析了超导La0.8Ca0.2NiO2和母体LaNiO2薄膜的低能谱函数。结果表明动量选择性关联和类边缘费米液体散射可在无明显类铜酸盐赝隙情况下发生，为识别高温超导正常态电子成分提供了基准。
英文摘要
Pseudogap formation, strange-metal behavior and unconventional superconductivity are closely intertwined in hole-doped cuprates, yet their relationship remains unresolved. Infinite-layer nickelates offer a distinct 3d9-derived platform to address this question by combining a cuprate-like Ni dx2-y2 Fermi surface with multiband electronic degrees of freedom. Here we use angle-resolved photoemission spectroscopy to resolve the low-energy spectral function of superconducting La0.8Ca0.2NiO2 and parent LaNiO2 thin films. In La0.8Ca0.2NiO2, the electronic self-energy Im Sigma(omega) is approximately linear in energy and its slope increases from (pi/2, pi/2) to (pi, 0), revealing momentum-dependent marginal-Fermi-liquid-like scattering. Both films show a progressive suppression of low-energy spectral weight from the diagonal direction toward (pi, 0), with stronger suppression in parent LaNiO2. However, finite Fermi-level spectral weight persists around the entire Fermi surface, with no leading-edge shift or back-bending indicative of pseudogap formation in either the electron pocket or the cuprate-like hole band. Our results demonstrate that momentum-selective correlations and marginal-Fermi-liquid-like scattering can occur without a detectable cuprate-like pseudogap, providing a benchmark for identifying the essential normal-state electronic ingredients of high-temperature superconductivity.
