Research Initiation Award: Computational Studies of 2D Magnetism of Chromium Triiodide

研究启动奖为传统黑人学院和大学的初级和中期职业教师提供支持，他们正在建立新的研究项目或重新指导和重建现有的研究项目。期望该奖项有助于提高教师的研究能力和效率，改善所在机构的研究和教学，并使本科生参与研究经验。该奖项授予温斯顿-塞勒姆州立大学有可能扩大在几个领域的影响。提出的工作将使用计算机模拟来了解感兴趣化合物的磁性。代表性不足的学生将接受计算化学方面的培训，这将在物理、化学、数学和计算机科学领域得到应用。PI将在课堂上使用他们的研究，每年将影响30个专业。研究结果可用于创新器件设计，造福社会。二维CrI3的本征铁磁性的发现是值得注意的，因为它在超紧凑传感器和存储模块中的潜在应用。但目前对二维磁性的了解是有限的：虽然研究人员一致认为材料中的磁相互作用是各向异性的，但关于其磁各向异性的起源有许多不同的观点，有些观点与其他观点相冲突。该项目旨在通过假设交换耦合和单离子各向异性来阐明2D CrI3中神秘的磁相互作用。通过密度泛函理论计算提取哈密顿系数，然后进行蒙特卡罗模拟，确定铁磁相变温度Tc。将进行自旋动力学模拟，以研究假设的各向异性是否会在维持二维CrI3中远程磁秩序所需的自旋波谱上引起间隙。更好地了解二维磁性意味着可以在创新设备设计中利用更多特性来造福社会。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Research Initiation Awards provide support for junior and mid-career faculty at Historically Black Colleges and Universities who are building new research programs or redirecting and rebuilding existing research programs. It is expected that the award helps to further the faculty member's research capability and effectiveness, improve research and teaching at the home institution, and involves undergraduate students in research experiences. The award to Winston-Salem State University has potential to broaden impacts in several areas. The proposed work will use computer simulations to understand magnetism in compounds of interest. Under-represented students will receive training in computational chemistry which will have applications in the fields of physics, chemistry, math and computer science. The PI will use their research in the classroom which will impact 30 majors each year. The results of the work could be used in innovative device design which will benefit society.The discovery of intrinsic ferromagnetism in 2D CrI3 is noteworthy because of its potential applications in ultra-compact sensors and memory modules. But current understanding about 2D magnetism is limited: while there is consensus among researchers that the magnetic interactions in the material are anisotropic, there are many different opinions, some in conflict with others, about the origin of its magnetic anisotropy. This project seeks to shed light on the enigmatic magnetic interactions in 2D CrI3 by hypothesizing both the exchange coupling and single-ion anisotropies. The Hamiltonian coefficients will be extracted by density functional theory calculations, and then be used to perform Monte Carlo simulations for deciding the ferromagnetic phase transition temperature Tc. Spin dynamics simulations will be carried out to investigate whether the hypothesized anisotropies induce a gap on the spin wave spectrum necessary for maintaining the long-range magnetic order in 2D CrI3. Better understanding about 2D magnetism means more features can be utilized in innovative device design to benefit society.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.