量子材料中的有序现象及其调控的研究进展

Research Progress in Quantum Materials: Ordering Phenomena and Their Manipulation

关联体系中多种量子有序态的竞争催生了极其丰富的物理性质和相图,对它们的研究将加深人们对量子材料中基本现象和规律的认识。而对量子序调控机制的研究,将有可能产生新的关键技术和新原理原型器件。本综述介绍了国家重点研发计划项目"关联体系多种量子有序态的竞争与调控"执行两年来,在量子材料的自旋量子纠缠序、向列序、电荷序、轨道序、超导序和拓扑序等多种量子有序态的机理与调控研究中取得的主要进展。着重介绍发现了多种基于有机-无机杂化结构的超导体系和一系列含稀土元素的新型铁基超导体,在自旋液体中发现分数化的激发,对FeSe1-xSx中向列序与超导序相互作用和Li0.8Fe0.2OHFeSe表面电子结构和超导电性的研究,对重费米子体系中电子的局域行为和巡游行为的相互作用的研究,以及实现了固体离子门电压的调控技术并得到了多种体系的相图等重要发现。这些研究成果加深了我们对量子序的认识,建立了研究和控制量子序的手段,也为未来量子序的应用打下了基础。

The competition of multiple quantum ordered states in correlated electron system results in rich physical properties and phase diagrams. It provides an opportunity to improve our understanding of the underlying physics in quantum materials. Moreover, the study of the tuning mechanism of quantum ordered states will also help us develop new key techniques as well as prototype devices. This review will introduce the main progress of quantum materials, which include the spin order with quantum entanglement, nematic order, charge order, orbital order, superconductivity and topological order, in the project "Competition and Manipulation of Quantum Ordered States in Correlated Electron Systems"(The National Key Research and Development Program of China) during the last two years. Below are the highlights of research progress, including the discovery of new superconductors with organic-inorganic hybrid structure or rare-earth elements, the fractionalized excitation in spin liquid, the interplay of nematic order and superconductivity in FeSe1-xSx, the surface electronic structure and superconductivity in Li0.8Fe0.2OHFeSe, the competition between localized and itinerant behaviors in heavy-fermion systems, and the realization of solid-ion-conductor gating technique and its application on the study of electronic phase diagram in several systems. These new results improve our understanding of quantum ordered states,help us develope new methods to explore quantum ordered states, and build a solid foundation for the application of quantum ordered states in the future.