Arouca R, Silva Neto M B, Chaves C M, Nagao M, Watauchi S, Tanaka I, ElMassalami M
Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, 21945-970 Rio de Janeiro, Brazil.
J Phys Condens Matter. 2017 Sep 6;29(35):355702. doi: 10.1088/1361-648X/aa7c37. Epub 2017 Jul 31.
Layered BiS -based series, such as LaO F BiS and Sr La FBiS , offer ideal examples for studying normal and superconducting phase diagram of a solid solution that evolves from a nonmagnetic band-insulator parent. We constructed typical [Formula: see text] phase diagrams of these systems based on events occurring in thermal evolution of their electrical resistivity, [Formula: see text]. Overall evolution of these diagrams can be rationalized in terms of (i) Mott-Efros-Shklovskii scenario which, within the semiconducting [Formula: see text] regime ([Formula: see text] metal-insulator transition), describes the doping influence on the thermally activated hopping conductivity. (ii) A granular metal (superconductor) scenario which, within [Formula: see text], describes the evolution of normal and superconducting properties in terms of conductance g, Coulomb charging energy E and Josephson coupling J; their joint influence is usually captured within a [Formula: see text] phase diagram. Based on analysis of the granular character of [Formula: see text], we converted the [Formula: see text] diagrams into projected g - T diagrams which, being fundamental, allow a better understanding of evolution of various granular-related properties (in particular the hallmarks of normal-state [Formula: see text] feature and superconductor-insulator transition) and how such properties are influenced by x, pressure or heat treatment.
基于层状BiS的系列材料，如LaO₁₋ₓFₓBiS₂和Sr₁₋ₓLaₓFₓBiS₂，为研究从非磁性带绝缘体母体演化而来的固溶体的正常和超导相图提供了理想的例子。我们根据其电阻率ρ(T)热演化过程中发生的事件，构建了这些系统的典型ρ-T相图。这些相图的整体演化可以根据以下方面进行合理化解释：(i) 莫特-埃弗罗斯-什克洛夫斯基（Mott-Efros-Shklovskii）情景，在半导体ρ(T)区域（ρ金属-绝缘体转变）内，描述了掺杂对热激活跳跃电导率的影响。(ii) 颗粒金属（超导体）情景，在ρ(T)内，根据电导g、库仑充电能量E和约瑟夫森耦合J描述正常和超导特性的演化；它们的联合影响通常在一个ρ-T相图中体现。基于对ρ(T)颗粒特性的分析，我们将ρ-T相图转换为投影g-T相图，这是基本的相图，有助于更好地理解各种与颗粒相关的特性（特别是正常态ρ(T)特征和超导体-绝缘体转变）的演化，以及这些特性如何受到x、压力或热处理的影响。
