石墨烯上铽原子的低能磁态

Monirul Shaikh, Alison Klein, Aleksander L. Wysocki
{"title":"石墨烯上铽原子的低能磁态","authors":"Monirul Shaikh, Alison Klein, Aleksander L. Wysocki","doi":"arxiv-2409.08079","DOIUrl":null,"url":null,"abstract":"Electronic structure and magnetic interactions of a Tb adatom on graphene are\ninvestigated from first principles using combination of density functional\ntheory and multiconfigurational quantum chemistry techniques including\nspin-orbit coupling. We determine that the six-fold symmetry hollow site is the\npreferred adsorption site and we investigate electronic spectrum for different\nadatom oxidation states including Tb$^{3+}$, Tb$^{2+}$, Tb$^{1+}$, and\nTb$^{0}$. For all charge states, the Tb $4f^8$ configuration is retained with\nother adatom valence electrons being distributed over $5d_{xy}$, $5d_{x2+y2}$,\nand $6s/5d_0$ single-electron orbitals. We find strong intra-site adatom\nexchange coupling that ensures that the $5d6s$ spins are parallel to the $4f$\nspin. For Tb$^{3+}$, the energy levels can be described by the $J=6$ multiplet\nsplit by the graphene crystal field. For other oxidation states, the\ninteraction of $4f$ electrons with spin and orbital degrees of freedom of\n$6s5d$ electrons in the presence of spin-orbit coupling results in the\nlow-energy spectrum composed closely lying effective multiplets that are split\nby the graphene crystal field. Stable magnetic moment is predicted for\nTb$^{3+}$ and Tb$^{2+}$ adatoms due to uniaxial magnetic anisotropy and\neffective anisotropy barrier around 440 cm$^{-1}$ controlled by the temperature\nassisted quantum tunneling of magnetization through the third excited doublet.\nOn the other hand, in-plane magnetic anisotropy is found for Tb$^{1+}$ and\nTb$^{0}$ adatoms. Our results indicate that the occupation of the $6s5d$\norbitals can dramatically affect the magnetic anisotropy and magnetic moment\nstability of rare earth adatoms.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Low-Energy Magnetic States of Tb Adatom on Graphene\",\"authors\":\"Monirul Shaikh, Alison Klein, Aleksander L. Wysocki\",\"doi\":\"arxiv-2409.08079\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Electronic structure and magnetic interactions of a Tb adatom on graphene are\\ninvestigated from first principles using combination of density functional\\ntheory and multiconfigurational quantum chemistry techniques including\\nspin-orbit coupling. We determine that the six-fold symmetry hollow site is the\\npreferred adsorption site and we investigate electronic spectrum for different\\nadatom oxidation states including Tb$^{3+}$, Tb$^{2+}$, Tb$^{1+}$, and\\nTb$^{0}$. For all charge states, the Tb $4f^8$ configuration is retained with\\nother adatom valence electrons being distributed over $5d_{xy}$, $5d_{x2+y2}$,\\nand $6s/5d_0$ single-electron orbitals. We find strong intra-site adatom\\nexchange coupling that ensures that the $5d6s$ spins are parallel to the $4f$\\nspin. For Tb$^{3+}$, the energy levels can be described by the $J=6$ multiplet\\nsplit by the graphene crystal field. For other oxidation states, the\\ninteraction of $4f$ electrons with spin and orbital degrees of freedom of\\n$6s5d$ electrons in the presence of spin-orbit coupling results in the\\nlow-energy spectrum composed closely lying effective multiplets that are split\\nby the graphene crystal field. Stable magnetic moment is predicted for\\nTb$^{3+}$ and Tb$^{2+}$ adatoms due to uniaxial magnetic anisotropy and\\neffective anisotropy barrier around 440 cm$^{-1}$ controlled by the temperature\\nassisted quantum tunneling of magnetization through the third excited doublet.\\nOn the other hand, in-plane magnetic anisotropy is found for Tb$^{1+}$ and\\nTb$^{0}$ adatoms. Our results indicate that the occupation of the $6s5d$\\norbitals can dramatically affect the magnetic anisotropy and magnetic moment\\nstability of rare earth adatoms.\",\"PeriodicalId\":501234,\"journal\":{\"name\":\"arXiv - PHYS - Materials Science\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-09-12\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"arXiv - PHYS - Materials Science\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/arxiv-2409.08079\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Materials Science","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2409.08079","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0

摘要

我们结合密度泛函理论和多构型量子化学技术(包括引脚轨道耦合),从第一性原理出发,研究了石墨烯上镱原子的电子结构和磁相互作用。我们确定六重对称空心位点是首选吸附位点,并研究了不同原子氧化态(包括 Tb$^{3+}$、Tb$^{2+}$、Tb$^{1+}$ 和 Tb$^{0}$)的电子能谱。在所有电荷态中,铽元素的 4f^8 元构型都被保留下来,其他原子价电子分布在 5d_{xy}$、5d_{x2+y2}$ 和 6s/5d_0$ 单电子轨道上。我们发现强烈的位内金刚石交换耦合确保了 5d6s$ 自旋与 4f$ 自旋平行。对于 Tb$^{3+}$,能级可以用石墨烯晶体场的 $J=6$ 多分叉来描述。对于其他氧化态,在存在自旋轨道耦合的情况下,4f$ 电子与 6s5d$ 电子的自旋和轨道自由度相互作用,产生了由石墨烯晶体场分割的紧密排列的有效多子构成的低能谱。由于单轴磁各向异性和大约 440 cm$^{-1}$ 的有效各向异性势垒受温度辅助的磁化量子隧穿第三激发双特的控制,因此可以预测锑$^{3+}$ 和锑$^{2+}$ 的原子具有稳定的磁矩。我们的研究结果表明,6s5d 原子轨道的占据会极大地影响稀土原子的磁各向异性和磁矩稳定性。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Low-Energy Magnetic States of Tb Adatom on Graphene
Electronic structure and magnetic interactions of a Tb adatom on graphene are investigated from first principles using combination of density functional theory and multiconfigurational quantum chemistry techniques including spin-orbit coupling. We determine that the six-fold symmetry hollow site is the preferred adsorption site and we investigate electronic spectrum for different adatom oxidation states including Tb$^{3+}$, Tb$^{2+}$, Tb$^{1+}$, and Tb$^{0}$. For all charge states, the Tb $4f^8$ configuration is retained with other adatom valence electrons being distributed over $5d_{xy}$, $5d_{x2+y2}$, and $6s/5d_0$ single-electron orbitals. We find strong intra-site adatom exchange coupling that ensures that the $5d6s$ spins are parallel to the $4f$ spin. For Tb$^{3+}$, the energy levels can be described by the $J=6$ multiplet split by the graphene crystal field. For other oxidation states, the interaction of $4f$ electrons with spin and orbital degrees of freedom of $6s5d$ electrons in the presence of spin-orbit coupling results in the low-energy spectrum composed closely lying effective multiplets that are split by the graphene crystal field. Stable magnetic moment is predicted for Tb$^{3+}$ and Tb$^{2+}$ adatoms due to uniaxial magnetic anisotropy and effective anisotropy barrier around 440 cm$^{-1}$ controlled by the temperature assisted quantum tunneling of magnetization through the third excited doublet. On the other hand, in-plane magnetic anisotropy is found for Tb$^{1+}$ and Tb$^{0}$ adatoms. Our results indicate that the occupation of the $6s5d$ orbitals can dramatically affect the magnetic anisotropy and magnetic moment stability of rare earth adatoms.
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信