磁电效应和磁热效应是当前磁性物理领域的研究热点。磁电效应可能为新型多功能电子学器件的设计提供了一个新的自由度，在自旋电子学、磁电传感器等领域有着广阔的潜在应用；大磁热效应探索可能为室温高效磁制冷提供解决方案。铁磁性的硫化物ACr2S4因巨磁阻效应、磁电耦合效应和大磁热效应的发现，逐渐得到研究者的重视。本项目将结合大磁电效应和大磁热效应的材料探索，在ACr2S4体系内，通过A位原子种类和成分的调控，系统地研究其晶体结构、磁结构和基本磁电性质随成分、温度、磁场和电场等演化的一般性规律。结合第一性原理计算，研究磁相互作用机制和自旋-晶格耦合的特征，深入理解系统的磁、电、热特性的物理本质，拓展人们对过渡金属化合物的结构与物性之间关系的认识，为寻找新型的磁电材料和磁热材料提供参考。

Magnetoelectric and magnetocaloric effects are hot topics in the field of mangetism and magnetic materials. Magnetoelectric effect has attractive potential application in spintronics and magnetoelectric sensor due to a novel degree of freedom added. Giant magnetocaloric effect near room temperature is expected to be applied in magnetic refrigerators and air conditioners with high energy efficiency. Ferromagnetic spinel sulfides ACr2S4 have recently attracted more attention due to the discovery of colossal magnetoresisitance, relaxation multiferrorics and large magnetic entropy change. In this project, we will focus on large magnetoelectric and magnetocaloric effects in ACr2S4, and investigate systematically the crystallographic and magnetic structures, properties of magnetic, transport and heat as a function of species and concentration of A-ion, temperature, magnetic field and electric field. In combination of the first principle calculation, the correlation among the subtle change of the local structure, magnetic exchange interaction, spin-lattice coupling and the properties will be interpreted.