集体输运导致的费米液体 $T^2$ 电阻率偏离
Deviation from Fermi-liquid $T^2$ resistivity caused by collective transport
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中文总结 AI 辅助
本文指出费米液体电阻率偏离 $T^2$ 行为在弱关联和强关联金属中符号相反，强关联金属中的向下偏离源于集体输运，与液体 $^3$He 类似，并在三种金属中观察到可比拟的过量电导。
中文摘要 AI 辅助
“费米液体行为”如今被用作电阻率随温度二次依赖关系的简称。在金属中，要实现这种行为，电子必须被冷却到远低于费米简并温度 $T_{\mathrm{F}}$ 的温度。在有限温度下，可以观察到对这种行为的偏离。在此，我们指出，这种偏离在两种不同类型的费米液体中具有相反的符号。在弱关联费米液体中，向上的偏离意味着非弹性电阻率的指数更高，这可归因于声子的\textit{额外散射}。相反，在强关联金属中则存在向下的偏离，这意味着\textit{散射减少}或\textit{额外导电}，正如在正常液体 $^3$He 中的情况，其中最近已识别出声模式对热输运的独特贡献。这种导电通道在 $T_{\mathrm{F}}$ 附近平滑地转变为经典液体热导率的布里奇曼公式所描述的通道。在三种金属（UPt$_3$、Sr$_2$RuO$_4$ 和重度过掺杂的 LSCO）中，根据现有实验数据，在 $T/T_{\mathrm{F}}\simeq0.02$ 时过量电导率的归一化幅度与在 $^3$He 中观察到的相当，这表明（但尚未证实）存在共同的起源。
英文摘要
`Fermi-liquid behavior' is nowadays used as a shorthand for quadratic temperature dependence of the electrical resistivity. In a metal, for this to occur, electrons must be cooled well below the Fermi degeneracy temperature, $T_{\mathrm{F}}$. A departure from this behavior is observed at finite temperature. Here, we note that this departure has opposite signs in two distinct types of Fermi liquids. In weakly correlated ones, the upward departure implies a higher exponent of the inelastic resistivity, attributable to \textit{additional scattering} by phonons. In contrast, there is a downward deviation in strongly correlated metals, which implies either \textit{reduced scattering} or \textit{additional conduction}, as in the case of normal liquid $^3$He, in which a distinct contribution to heat transport by a sound mode has been recently identified. Such a channel of conduction smoothly transforms across $T_{\mathrm{F}}$ to the one captured by the Bridgman formula for thermal conductivity of classical liquids. In three metals (UPt$_3$, Sr$_2$RuO$_4$, and heavily overdoped LSCO), according to the available experimental data, the normalized amplitude of excess conductivity at $T/T_{\mathrm{F}}\simeq0.02$ is comparable to what has been seen in $^3$He, suggesting, without establishing, a common origin.
发表机构
- Laboratoire de Physique et d’Étude des Matériaux (ESPCI - CNRS - Sorbonne Université), PSL Research University（材料物理与研究所（ESPCI - 法国国家科学研究中心 - 索邦大学），巴黎文理研究大学）
机构由 AI 辅助整理，请以论文原文为准。
