论文标题
Terahertz混合价值YBAL $ _3 $的电动力学和lual $ _3 $薄膜
Terahertz Electrodynamics of Mixed-Valent YbAl$_3$ and LuAl$_3$ Thin Films
论文作者
论文摘要
我们介绍了混合价值Ybal $ _3 $及其结构模拟Lual $ _3 $的薄膜的测量。结合传统的傅立叶变换红外（FTIR）光谱法，扩展的Drude形式主义可用于研究这些材料的低频运输。我们发现lual $ _3 $显示了常规的drude运输，而在低温下，ybal $ _3 $显示出急剧重生的drude峰和电导率中的中含量（mir）峰，表明形成了沉重的费米液体。在ybal $ _3 $中，扩展的Drude框架显示出散射率的一致性，而费米 - 液体行为低于$ t <40 $ k和适度的质量增强。虽然尚未明确表现出$ω^2 $ fermi液体样的频率依赖性，但drude散射速率和有效质量的温度依赖性与低温中等沉重的费米液体的形成是一致的，尽管一个液体的质量比单晶中观察到的小。扩展的Drude分析还支持YBAL $ _3 $之间的费米液态状态与正常状态之间的慢速交叉。
We present THz measurements of thin films of mixed-valent YbAl$_3$ and its structural analogue LuAl$_3$. Combined with traditional Fourier transform infrared (FTIR) spectroscopy, the extended Drude formalism is utilized to study the low-frequency transport of these materials. We find that LuAl$_3$ demonstrates conventional Drude transport whereas at low temperatures YbAl$_3$ demonstrates a sharply renormalized Drude peak and a mid-infrared (MIR) peak in the conductivity, indicative of the formation of a heavy Fermi liquid. In YbAl$_3$ the extended Drude framework shows a consistency of the scattering rate with Fermi-liquid behavior below $T < 40$ K and a moderate mass enhancement. While a $ω^2$ Fermi liquid-like frequency dependence is not clearly exhibited, the temperature dependence of the Drude scattering rate and effective mass is consistent with the formation of a low-temperature moderately heavy Fermi liquid, albeit one with a smaller mass than observed in single crystals. The extended Drude analysis also supports a slow crossover between the Fermi liquid state and the normal state in YbAl$_3$.
