Scattering by slowly fluctuating degrees of freedom can cause a transient localization of the current-carrying electrons in metals, driving the system away from normal metallic behavior. We illustrate and characterize this general phenomenon by studying how signatures of localization emerge in the optical conductivity of electrons interacting with slow bosonic fluctuations. The buildup of quantum localization corrections manifests itself in the emergence of a displaced Drude peak (DDP), whose existence strongly alters the low frequency optical response and suppresses the d.c. conductivity. We find that for sufficiently strong interactions, many-body renormalization of the fluctuating field induced at metallic densities enhances electron localization and the ensuing DDP phenomenon in comparison with the well-studied low concentration limit. Our results are compatible with the frequent observation of DDPs in electronic systems where slowly fluctuating degrees of freedom couple significantly to the charge carriers.

中文翻译：

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从缓慢波动的相互作用中取代德鲁德峰和劣质金属。

缓慢波动的自由度造成的散射会导致金属中载流电子的瞬态定位，从而使系统偏离正常的金属行为。我们通过研究电子的光导率如何与缓慢的玻色子波动相互作用来说明和表征这种一般现象。量子局域化校正的积累体现在位移的德鲁德峰 (DDP) 的出现，它的存在强烈地改变了低频光学响应并抑制了直流电导率。我们发现，对于足够强的相互作用，与充分研究的低浓度极限相比，在金属密度下引起的波动场的多体重整化增强了电子局部化和随之而来的 DDP 现象。