Kumar Upendra, Sreenivasa Reddy P V, Bhattacharjee Satadeep, Lee Seung-Cheol
Indo-Korea Science and Technology Center (IKST), New Airport Road, Yelahanka, Bangalore, 560065, India.
J Phys Condens Matter. 2019 Aug 21;31(33):335702. doi: 10.1088/1361-648X/ab2089. Epub 2019 May 9.
First principles studies were performed in order to find out the possibility of inducing half-metallicity in Heusler Compound CoFeMnSb, by means of alloying it with 3d-transition metal elements. Proper alloying element is selected through the calculations of formation energies. These calculations were tested with different concentrations of alloying elements at different atomic sites. Among the selected transition metal elements Sc and Ti are proposed to be excellent alloying elements, particularly at Mn site. By using these alloying elements complete half metallic behaviour is obtained in [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and CoFeTiSb alloys. Shifting of Co-Fe d-states towards lower energy region leads to zero density of states at Fermi level for the spin minority channel. Alloying effects on the electronic structure and magnetization are discussed in details. Thermodynamical stability of these new alloys is a major part of this study. The Curie temperatures of [Formula: see text] and [Formula: see text] were found to be 324.5 K and 682 K; respectively, showing good candidature for spintronics applications. For understanding the bonding nature of the constituent atom of CoFeMnSb, crystal orbital Hamiltonian populations have been analysed.
为了探究通过将赫斯勒化合物CoFeMnSb与3d过渡金属元素合金化来诱导其半金属性的可能性,进行了第一性原理研究。通过形成能的计算来选择合适的合金元素。这些计算在不同原子位置的不同合金元素浓度下进行了测试。在所选择的过渡金属元素中,钪(Sc)和钛(Ti)被认为是优异的合金元素,特别是在锰(Mn)位置。通过使用这些合金元素,在[化学式:见原文]、[化学式:见原文]、[化学式:见原文]、[化学式:见原文]、[化学式:见原文]和CoFeTiSb合金中获得了完全的半金属行为。钴(Co)-铁(Fe)d态向较低能量区域的移动导致自旋少数通道在费米能级处的态密度为零。详细讨论了合金化对电子结构和磁化的影响。这些新合金的热力学稳定性是本研究的重要部分。发现[化学式:见原文]和[化学式:见原文]的居里温度分别为324.5 K和682 K,显示出在自旋电子学应用中的良好潜力。为了理解CoFeMnSb组成原子的键合性质,对晶体轨道哈密顿布居进行了分析。