Strong manipulation of the valley splitting upon twisting and gating in MoSe2/CrI3 and WSe2/CrI3

物理 凝聚态物理 哈密顿量(控制论) 异质结 联轴节(管道) 材料科学 结晶学 化学 数学 数学优化 冶金
作者
Klaus Zollner,Paulo E. Faria,Jaroslav Fabian
出处
期刊:Physical review [American Physical Society]
卷期号:107 (3) 被引量:23
标识
DOI:10.1103/physrevb.107.035112
摘要

Van der Waals (vdW) heterostructures provide a rich playground to engineer electronic, spin, and optical properties of individual two-dimensional materials. We investigate the twist-angle and gate dependence of the proximity-induced exchange coupling in the monolayer transition-metal dichalcogenides (TMDCs) ${\mathrm{MoSe}}_{2}$ and ${\mathrm{WSe}}_{2}$ due to the vdW coupling to the ferromagnetic semiconductor ${\mathrm{CrI}}_{3}$, from first-principles calculations. A model Hamiltonian, which captures the relevant band edges at the $K/{K}^{\ensuremath{'}}$ valleys of the proximitized TMDCs, is employed to quantify the proximity-induced exchange. Upon twisting from ${0}^{\ensuremath{\circ}}$ to ${30}^{\ensuremath{\circ}}$, we find a transition of the TMDC valence band (VB) edge exchange splitting from about $\ensuremath{-}2$ to $2\phantom{\rule{4pt}{0ex}}\mathrm{meV}$, while the conduction band (CB) edge exchange splitting remains nearly unchanged at around $\ensuremath{-}3\phantom{\rule{4pt}{0ex}}\mathrm{meV}$. For the VB of ${\mathrm{WSe}}_{2}$ (${\mathrm{MoSe}}_{2}$) on ${\mathrm{CrI}}_{3}$, the exchange coupling changes sign at around ${8}^{\ensuremath{\circ}}$ (${16}^{\ensuremath{\circ}}$). We find that even at the angles with almost zero spin splittings of the VB, the real-space spin polarization profile of holes at the band edge is highly nonuniform, with alternating spin up-and spin-down orbitals. Furthermore, a giant tunability of the proximity-induced exchange coupling is provided by a transverse electric field of a few V/nm. Within our first-principles framework, we are limited to commensurate structures, and thus considered a maximum strain of 2.2% for the individual monolayers. By investigating different atomic stacking configurations of the strained supercells, we demonstrate that proximity exchange varies locally in space within experimentally realistic setups. We complement our ab initio results by calculating the excitonic valley splitting to provide experimentally verifiable optical signatures of the proximity exchange. Specifically, we predict that the valley splitting increases almost linearly as a function of the twist angle. Furthermore, the proximity exchange is highly tunable by gating, allowing to tailor the valley splitting in the range of 0 to 12 meV in ${\mathrm{WSe}}_{2}/{\mathrm{CrI}}_{3}$, which is equivalent to external magnetic fields of up to about 60 T. Our results highlight the important impact of the twist angle and gating when employing magnetic vdW heterostructures in experimental geometries.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
AaronDP发布了新的文献求助10
1秒前
2秒前
顾矜应助淡然妙竹采纳,获得10
2秒前
KingYugene完成签到,获得积分10
2秒前
花藏影完成签到 ,获得积分10
3秒前
3秒前
Miranda完成签到,获得积分10
4秒前
SciGPT应助哈比人linling采纳,获得10
5秒前
kk119完成签到,获得积分10
5秒前
Coai517完成签到 ,获得积分10
6秒前
6秒前
小甘发布了新的文献求助10
7秒前
TG_FY完成签到,获得积分10
7秒前
yuan完成签到,获得积分10
8秒前
橙子完成签到,获得积分10
8秒前
谦让之云完成签到 ,获得积分10
8秒前
8秒前
愉快书琴完成签到,获得积分10
9秒前
9秒前
SYLH应助WangZhen采纳,获得10
10秒前
福尔摩云完成签到,获得积分10
11秒前
无辜的秀完成签到,获得积分10
12秒前
Charles完成签到,获得积分10
14秒前
hao发布了新的文献求助10
14秒前
小嘎发布了新的文献求助10
14秒前
ABin完成签到,获得积分10
16秒前
Jasper应助qixiaoqi采纳,获得10
16秒前
FangyingTang完成签到 ,获得积分10
17秒前
金枪鱼子完成签到,获得积分10
17秒前
theyoung发布了新的文献求助10
17秒前
18秒前
量子星尘发布了新的文献求助10
18秒前
赘婿应助liu采纳,获得10
18秒前
小马甲应助清仔采纳,获得10
18秒前
18秒前
luoyue完成签到,获得积分10
18秒前
yuan发布了新的文献求助10
19秒前
科研通AI5应助JR采纳,获得30
19秒前
20秒前
海阔天空发布了新的文献求助10
21秒前
高分求助中
【提示信息,请勿应助】关于scihub 10000
Les Mantodea de Guyane: Insecta, Polyneoptera [The Mantids of French Guiana] 3000
徐淮辽南地区新元古代叠层石及生物地层 3000
The Mother of All Tableaux: Order, Equivalence, and Geometry in the Large-scale Structure of Optimality Theory 3000
Global Eyelash Assessment scale (GEA) 1000
Picture Books with Same-sex Parented Families: Unintentional Censorship 550
Research on Disturbance Rejection Control Algorithm for Aerial Operation Robots 500
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 4038619
求助须知:如何正确求助?哪些是违规求助? 3576294
关于积分的说明 11375058
捐赠科研通 3306084
什么是DOI,文献DOI怎么找? 1819374
邀请新用户注册赠送积分活动 892698
科研通“疑难数据库(出版商)”最低求助积分说明 815066