AI 中文总结
本研究针对铜基超导体中红外光导率的普适特征，基于哈伯德模型提出其源于赝能隙与莫特-哈伯德能隙，通过数值和解析方法确定能隙的掺杂依赖性，为该现象提供统一微观理解。
AI 中文摘要
铜基超导体的中红外（MIR）光导率呈现出普适特征，本研究证实这些特征源于两种不同的能隙：由反铁磁自旋涨落介导的赝能隙，以及莫特-哈伯德能隙。这两种能隙对应的中红外光谱具有特征性且截然不同的形状和掺杂依赖性，因此可被区分。具体而言，莫特-哈伯德关联在低掺杂时会在可见光波段产生一个峰，而在高掺杂时，当单粒子谱中出现“瀑布”结构时，会产生从中红外开始的宽光学响应。通过数值和解析方法确定的两种能隙的掺杂依赖性与实验结果一致，为铜基中红外光导率提供了统一的微观理解。
英文摘要
Mid-infrared (MIR) optical conductivities in cuprate superconductors show universal features. In this study, we demonstrate that these originate from two distinct gaps: the pseudogap mediated by antiferromagnetic spin fluctuations and the Mott-Hubbard gap. The MIR spectra from these two gaps show a characteristic and distinct shape and doping dependence, and can thus be distinguished. Specifically, the Mott-Hubbard correlations, while rendering a peak in the visible spectrum for small dopings, yield a broad optical response starting in the MIR when a ``waterfall'' develops in the one-particle spectrum at larger dopings. The numerically and analytically determined doping-dependence of both gaps consistently reproduce experiments, and provide a unified microscopic understanding of the cuprate MIR optical conductivity.
