Muhammad Zahir, Ali Muhammad Waqas, Mir Irshad A, Khan Qudrat Ullah, Zhu Ling
College of Physics and Optoelectronic Engineering, Shenzhen University, Nanhai Ave. 3688, Shenzhen, Guangdong 518060, People's Republic of China.
Nanotechnology. 2020 Mar 20;31(23):235704. doi: 10.1088/1361-6528/ab72b3. Epub 2020 Feb 4.
Two-dimensional (2D) magnetic layered materials have attracted considerable attention in memory storage devices due to their exciting magnetic ordering. Herein, the electronic and magnetic properties of high-quality single crystals zirconium diselenide and copper (Cu)-doped zirconium diselenide as grown via chemical vapor transport technique combined with first principle density functional theory calculations were investigated. A semimetallic state is recognized for CuZrSe as measured through resistance versus temperature measurements and angle resolved photoemission spectroscopy (ARPES). The magnetic measurement shows diamagnetic semiconducting behaviour for ZrSe, whereas CuZrSe exhibits ferromagnetic character via applying perpendicular magnetic field. CuZrSe reveals the room temperature magnetic moment ∼0.0125 emu g, while the Curie temperature is ∼363.49 K. Furthermore, first principle density functional theory (DFT) calculations show energetically long range ferromagnetic ordering in a half-metallic Cu-doped ZrSe, while a diamagnetic state in case of ZrSe agrees well with experiment results. These results suggest that due to strong interaction elements at the octahedral site of zirconium atoms when replaced by copper atoms, which can change the spin ordering of electrons and make zirconium vacancy, while their magnetic moment is increased. Very importantly the half-metallic character of CuZrSe promotes much spin polarized electrons around the Fermi level, suggesting significant potential in future memory devices and spintronic applications.
二维(2D)磁性层状材料因其令人兴奋的磁有序性而在存储设备中引起了相当大的关注。在此,通过化学气相传输技术生长的高质量单晶二硒化锆和铜(Cu)掺杂的二硒化锆的电子和磁性特性,并结合第一性原理密度泛函理论计算进行了研究。通过电阻与温度测量以及角分辨光电子能谱(ARPES)测量发现,CuZrSe呈现半金属态。磁性测量表明ZrSe具有抗磁半导体行为,而CuZrSe在施加垂直磁场时表现出铁磁特性。CuZrSe在室温下的磁矩约为0.0125 emu g,居里温度约为363.49 K。此外,第一性原理密度泛函理论(DFT)计算表明,在半金属Cu掺杂的ZrSe中存在能量上的长程铁磁有序,而ZrSe的抗磁态与实验结果吻合良好。这些结果表明,由于锆原子八面体位置的强相互作用元素被铜原子取代时,会改变电子的自旋排序并产生锆空位,同时其磁矩增加。非常重要的是,CuZrSe的半金属特性在费米能级周围促进了大量自旋极化电子,这表明其在未来存储设备和自旋电子学应用中具有巨大潜力。