Tunable magnetism in layered CoPS3 by pressure and carrier doping

层状CoPS3中磁性的压力与载流子掺杂可控调节

Despite extensive research on recently discovered layered ferromagnetic(FM)materials,their further development is hampered by the limited number of candidate materials with desired properties.As a much bigger family,layered antiferromagnetic(AFM)materials represent excellent platforms to not only deepen our understanding of fundamental physics but also push forward high-performance spintronics applications.Here,by systematic first-principles calculations,we demonstrate pressure and carrier doping control of magnetic properties in layered AFM CoPS3,a representative of transition metal phosphorus trichalcogenides.In particular,pressure can drive isostructural Mott transition,in sharp contrast to other transition metal thiophosphates.Intriguingly,both pressure and carrier doping can realize the long-sought FM half-metallic states with 100%spin polarization percentage,which is good for improving the injection and detection efficiency of spin currents among others.Moreover,the Mott transition is accompanied by instantaneous spin-crossover(SCO)in CoPS3,and such cooperative SCO facilitates the implementation of fast-response reversible devices,such as data storage devices,optical displays and sensors.We further provide an in-depth analysis for the mechanisms of FM half-metallicity and SCO.Tunable magnetism in layered AFM materials opens vast opportunities for purposeful device design with various functionalities.

最近发现的层状铁磁材料吸引了研究者的广泛兴趣,但是其有限的数量严重阻碍了进一步的发展.作为一个更大的家族,层状反铁磁材料为加深对基本磁性物理的理解和推动高性能自旋电子学的应用提供了一个出色的平台.本文中,我们选取了过渡金属磷三硫族化合物中代表性的反铁磁CoPS3材料,并通过系统的第一性原理计算证实压力或载流子掺杂可有效调控它的磁性.特别地,压力可以驱动其同构的Mott相变,这与其他过渡金属磷三硫族化合物形成了鲜明的对比.有趣的是,压力和载流子掺杂都可以实现具有100%自旋极化率的铁磁半金属态,研究人员长期寻求的这种特殊铁磁态有助于提高自旋电流的注入和检测效率.此外,Mott相变伴随着CoPS3中的瞬时自旋交叉,这样的协同自旋交叉有利于实现快速响应的可逆电子设备,如数据存储设备、光学显示器和传感器等.我们还进一步对铁磁半金属性及自旋交叉的机理进行了深入的分析.本文所预测的CoPS3材料的可调磁性、铁磁半金属性和自旋交叉,为各种功能设备的设计提供了广阔的空间.