离子注入（铌和钴）二硫化钼晶体中的巨磁化强度和大矫顽力

Colossal Magnetization and Giant Coercivity in Ion-Implanted (Nb and Co) MoS Crystals.

作者信息

Ahmed Sohail, Carl Cui Xiang-Yuan, Ding Xiang, Murmu Peter Paul, Bao Nina, Geng Xun, Xi Shibo, Liu Rong, Kennedy John, Wu Tom, Wang Lan, Suzuki Kiyonori, Ding Jun, Chu Xueze, Clastinrusselraj Indirathankam Sathish Russellraj, Peng Mingli, Vinu Ajayan, Ringer Simon Peter, Yi Jiabao

机构信息

School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia.

Australian Centre for Microscopy & Microanalysis, and School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia.

出版信息

ACS Appl Mater Interfaces. 2020 Dec 30;12(52):58140-58148. doi: 10.1021/acsami.0c18150. Epub 2020 Dec 16.

DOI:10.1021/acsami.0c18150

PMID:33375795

Abstract

Colossal saturation magnetization and giant coercivity are realized in MoS single crystals doped with Nb and/or Co using an ion implantation method. Magnetic measurements have demonstrated that codoping with 2 at % Nb and 4 at % Co invoked a "giant" coercivity, as high as 9 kOe at 100 K. Doping solely with 5 at % Nb induces a "colossal" magnetization of 1800 emu/cm at 5 K, which is higher than that of metallic Co. The high magnetization is due to the formation of Nb-rich defect complexes, as confirmed by first-principles calculations. It is proposed that the high coercivity is due to the combined effects of strong directional exchange coupling induced by the Nb and Co doping and pinning effects from defects within the layered structure. This high magnetization mechanism is also applicable to 2D materials with bilayers or few layers of thickness, as indicated by first-principles calculations. Hence, this work opens a potential pathway for the development of 2D high-performance magnetic materials.

摘要

通过离子注入法在掺杂了铌（Nb）和/或钴（Co）的二硫化钼（MoS）单晶中实现了巨大的饱和磁化强度和高矫顽力。磁性测量表明，2原子百分比的Nb和4原子百分比的Co共掺杂产生了“巨大”的矫顽力，在100 K时高达9 kOe。仅掺杂5原子百分比的Nb在5 K时会诱导出1800 emu/cm的“巨大”磁化强度，这高于金属Co的磁化强度。第一性原理计算证实，高磁化强度归因于富含Nb的缺陷复合体的形成。有人提出，高矫顽力是由于Nb和Co掺杂引起的强方向交换耦合以及层状结构内缺陷的钉扎效应共同作用的结果。第一性原理计算表明，这种高磁化机制也适用于具有双层或几层厚度的二维材料。因此，这项工作为二维高性能磁性材料的开发开辟了一条潜在途径。