论文标题
铁电金属中各向异性电阻率和超导不稳
Anisotropic resistivity and superconducting instability in ferroelectric metals
论文作者
论文摘要
我们提出了一种铁电金属的理论模型，其中自发的电偏振与导电电子共存。在我们的模型中，我们在导出电子与两个软横向光学声子相互作用时采用一种情况，将其推广到系统中自发的铁电偏振时的情况下，并表明与声音的线性耦合结果出现。我们发现，这种耦合导致各向异性电运转运，该电动运输具有当前电压下降的横向。重要的是，电阻率的横向分量与温度具有不同的线性依赖性。此外，我们表明耦合增强了铁电金属的超导过渡温度。我们认为，我们的结果有助于解释有关铁电钛酸腹酯的最新实验，并提供了新的实验特征。
We propose a theoretical model of a ferroelectric metal where spontaneous electric polarization coexists with the conducting electrons. In our model we adopt a scenario when conducting electrons interact with two soft transverse optical phonons, generalize it to the case when there is a spontaneous ferroelectric polarization in the system, and show that a linear coupling to the phonons emerges as a result. We find that this coupling results in anisotropic electric transport which has a transverse to the current voltage drop. Importantly, the obtained transverse component of the resistivity has distinct linear dependence with temperature. Moreover, we show that the coupling enhances superconducting transition temperature of the ferroelectric metal. We argue that our results help to explain recent experiments on ferroelectric strontium titanate, as well as provide new experimental signatures to look for.
