反铁磁体系量子态的高压调控和与其相关的超导电性的研究

We will investigate the quantum state and related superconductivity in anti-ferromagnetic systems by using an advanced self-made experimental system integrated with high pressure, low temperature and magnetic field, in combination with the techniques of in-situ high pressure synchrotron radiation and neutron scattering. Our attentions will focus on some important issues in the field of high-Tc superconductivity research, including pressure tuning of the quantum state in Mn-based anti-ferromagnetic systems to see its possibility of superconductivity; Similarity and dissimilarity of high pressure influence on anti-ferromagnetic order degree and superconductivity in Cu-based, Fe-based and Mn-based systems; the effects of pressure on interlayer coupling. In this project, we will adopt a unique way - high pressure ,the large energy scale method, to tune the quantum state of the systems investigated, in order to find novel phenomena, impel the field moving forward and provide useful information of pressure dimension for searching new superconductors. Simultaneity, this interdisciplinary project will upgrade our capability of the high pressure study on the frontiers of superconductivity. Our team have made important contributions to the studies of cuprates and Fe-based superconductors, and achieved significant progress in the studies on pressure-tuned quantum transition and superconductivity in FeSe-based superconductors recently, all of which insure the feasibility of this proposed project.

本项目团队拟采用自行研制的、先进的高压-低温-磁场联合测量系统并结合高压同步辐射和中子散射测量技术，对反铁磁体系的量子态和与其相关的超导电性进行深入研究。重点研究目前高温超导研究领域的几个热点问题，包括对锰基反铁磁体系量子态的压力调控和其潜在的超导电性的研究；铜基、铁基和锰基等不同体系中的反铁磁性对超导电性影响的异同及对比研究；压力对反铁磁体系中层间耦合影响的研究等。本项目拟通过独特的大能量尺度压力调控方法对研究体系的量子态进行调控，从中发现新现象、争取实现新突破，并为新型高温超导体的探索研究提供引导。同时，通过开展这种交叉学科的研究，提升我国利用高压等综合极端条件与测试技术开展高水平研究的能力，使我国在该领域的研究处于领先地位。本课题组曾在铜氧化物和铁基高温超导体的研究中做出了突出贡献，尤其近年来在高压量子调控及高压超导电性研究方面又取得了多项重要进展，这些积累确保了项目的可行性。

本项目在基金委的大力支持下采用课题组现有超高压、低温、强磁场联合测试系统围绕反铁磁体系量子态的高压调控和与其相关的超导电性等一系列重要问题对锰基、铁基和其它具有层状结构的反铁磁化合物体系的量子态和相关超导电性等方面开展了系列研究，并结合同步辐射大科学装置对以上材料开展了高压原位谱学实验，全面探索压力对电子关联体系的磁有序及相关的量子相变等的影响。本项目顺利完成了项目预期的科学目标，取得了系列研究成果。