Current-induced circular dichroism on metallic surfaces: A first-principles study.

IF 3.2 2区 物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY
Farzad Mahfouzi, Mark D Stiles, Paul M Haney
{"title":"Current-induced circular dichroism on metallic surfaces: A first-principles study.","authors":"Farzad Mahfouzi, Mark D Stiles, Paul M Haney","doi":"10.1103/physrevb.111.014415","DOIUrl":null,"url":null,"abstract":"<p><p>We use <i>ab initio</i> calculations to evaluate the current-induced optical response and orbital moment accumulation at the surfaces of metallic films. These two quantities are related by a sum rule that equates the circular dichroic absorption integrated over frequency to the gauge-invariant self-rotation contribution to the orbital magnetization, <math> <msub> <mrow> <mover><mrow><mi>M</mi></mrow> <mo>→</mo></mover> </mrow> <mrow><mtext>SR</mtext></mrow> </msub> </math> . In typical ferromagnets, <math> <msub> <mrow> <mover><mrow><mi>M</mi></mrow> <mo>→</mo></mover> </mrow> <mrow><mtext>SR</mtext></mrow> </msub> </math> is a good approximation to the total orbital magnetization. We compute the current-induced <math> <msub> <mrow> <mover><mrow><mi>M</mi></mrow> <mo>→</mo></mover> </mrow> <mrow><mtext>SR</mtext></mrow> </msub> </math> for a Pt thin film and compare it to the current-induced orbital moment accumulation calculated with the atom-centered approximation (ACA). We find significant differences: the size of <math> <msub> <mrow> <mover><mrow><mi>M</mi></mrow> <mo>→</mo></mover> </mrow> <mrow><mtext>SR</mtext></mrow> </msub> </math> is, in general, larger than the ACA orbital moment accumulation by an order of magnitude and includes substantial finite-size effects. The differences between the two quantities caution against interpreting optical measurements with models utilizing the ACA. Finally, we compute the total surface <math> <msub> <mrow> <mover><mrow><mi>M</mi></mrow> <mo>→</mo></mover> </mrow> <mrow><mtext>SR</mtext></mrow> </msub> </math> and ACA orbital moment accumulation as a function of layer thickness. For both quantities, the length scale at which the total surface accumulation saturates is on the order of the mean free path and longer than the length scale of their spatial profiles.</p>","PeriodicalId":48701,"journal":{"name":"Physical Review B","volume":"111 1","pages":""},"PeriodicalIF":3.2000,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11833748/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical Review B","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1103/physrevb.111.014415","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0

Abstract

We use ab initio calculations to evaluate the current-induced optical response and orbital moment accumulation at the surfaces of metallic films. These two quantities are related by a sum rule that equates the circular dichroic absorption integrated over frequency to the gauge-invariant self-rotation contribution to the orbital magnetization, M SR . In typical ferromagnets, M SR is a good approximation to the total orbital magnetization. We compute the current-induced M SR for a Pt thin film and compare it to the current-induced orbital moment accumulation calculated with the atom-centered approximation (ACA). We find significant differences: the size of M SR is, in general, larger than the ACA orbital moment accumulation by an order of magnitude and includes substantial finite-size effects. The differences between the two quantities caution against interpreting optical measurements with models utilizing the ACA. Finally, we compute the total surface M SR and ACA orbital moment accumulation as a function of layer thickness. For both quantities, the length scale at which the total surface accumulation saturates is on the order of the mean free path and longer than the length scale of their spatial profiles.

金属表面电流诱导的圆二色性:第一性原理研究。
我们用从头算法计算了金属薄膜表面的电流诱导光学响应和轨道矩积累。这两个量通过一个求和规则联系起来,该求和规则等于圆二向色吸收随频率的积分与标准不变自旋对轨道磁化的贡献M→SR。在典型的铁磁体中,M→SR是一个很好的轨道总磁化强度近似值。我们计算了铂薄膜的电流诱导M→SR,并将其与用原子中心近似(ACA)计算的电流诱导轨道矩积累进行了比较。我们发现了显著的差异:M→SR的大小通常比ACA轨道矩积累大一个数量级,并且包含大量的有限尺寸效应。这两个量之间的差异对利用ACA的模型解释光学测量结果提出了警告。最后,我们计算了总表面M→SR和ACA轨道矩累积作为层厚的函数。对于这两个量,表面总积累饱和的长度尺度都在平均自由程的量级上,并且比它们的空间剖面的长度尺度更长。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Physical Review B
Physical Review B PHYSICS, CONDENSED MATTER-
CiteScore
6.30
自引率
32.40%
发文量
4177
期刊介绍: Physical Review B (PRB) is the world’s largest dedicated physics journal, publishing approximately 100 new, high-quality papers each week. The most highly cited journal in condensed matter physics, PRB provides outstanding depth and breadth of coverage, combined with unrivaled context and background for ongoing research by scientists worldwide. PRB covers the full range of condensed matter, materials physics, and related subfields, including: -Structure and phase transitions -Ferroelectrics and multiferroics -Disordered systems and alloys -Magnetism -Superconductivity -Electronic structure, photonics, and metamaterials -Semiconductors and mesoscopic systems -Surfaces, nanoscience, and two-dimensional materials -Topological states of matter
×
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