论文标题
BAPB $ _ {0.75} $ bi $ $ _ {0.25} $ o $ $ $ _3 $的晶格应变的证据
Evidence of Lattice Strain as a Precursor to Superconductivity in BaPb$_{0.75}$Bi$_{0.25}$O$_3$
论文作者
论文摘要
在这项工作中，我们使用温度依赖电阻率，X射线衍射技术和光疗法光谱法研究了BAPB $ _ {0.75} $ bapb $ _ {0.75} $ ba $ $ _ {0.25} $ _3 $的前体效应的前体效应。目前的化合物在11 K（$ T_C $）左右表现出超导性。与文献中可用的过程相比，采用的综合程序要简单得多。在温度范围（10 k-25 K），即高于$ t_c $的情况下，我们的结果表明，正骨和四方菌株的增加。 BI和PB 4 $ F_ {7/2} $核心水平在BI和PB 4中观察到的良好筛选功能表示样品的金属性质。该化合物在300 K时在费米水平上表现出有限的强度，并且这种强度随温度降低而降低，并发展为伪群。状态光谱密度的能量依赖性表明金属状态无序。此外，我们的频带结构计算表明，PB掺杂的结构过渡会导致在费米水平上闭合带隙。
In this work, we have investigated the precursor effects to superconductivity in BaPb$_{0.75}$Bi$_{0.25}$O$_3$ using temperature dependent resistivity, x-ray diffraction technique and photoemission spectroscopy. The present compound exhibits superconductivity around 11 K ($T_C$). The synthesis procedure adopted is much simpler as compared to the procedure available in the literature. In the temperature range (10 K-25 K) i.e. above $T_C$, our results show an increase in both the orthorhombic and tetragonal strain. The well screened features observed in Bi and Pb 4$f_{7/2}$ core levels are indicative of the metallic nature of the sample. The compound exhibits finite intensity at the Fermi level at 300 K and this intensity decreases with decrease in temperature and develops into a pseudogap; the energy dependence of the spectral density of states suggests disordered metallic state. Furthermore, our band structure calculations reveal that the structural transition upon Pb doping results in the closing of the band gap at the Fermi level.
