SlideShare a Scribd company logo
1 of 24
Download to read offline
レーザー誘起マグノントポロジカル絶縁体
仲田光樹, Se Kwon Kim, 高吉慎太郎
A B C
原子力機構先端研, Missouri大, マックス・プランク研 MPI-PKS
A B C
JPS Nagoya 2019 JPS: 18pE25-11
KN, Kim, and Takayoshi, PRB 100, 014421 (2019)
cf., see also;
Kim, KN, Loss, and Tserkovnyak, PRL 122, 057204 (2019):
KN, Kim, Klinovaja, and Loss, PRB 96, 224414 (2017):
KN, Klinovaja, and Loss, PRB 95, 125429 (2017):
フェリ磁性体
反強磁性体
強磁性体
GOAL
スピントロニクス 量子光学
トポロジカルスピン流物性:光デザイン・レーザー制御
トポロジカル物理
光学的スピントロニクス
確立: スピン流制御 by レーザー
𝜇B
マグノン
磁性絶縁体中のスピン角運動量の運び屋
電子
𝜇B
マグノン
𝑒
Fermion Boson
量子輸送物性
Pauliの排他原理有 無
電子輸送 𝑒
Fermion
マグノン輸送 𝜇B
Boson
Wiedemann-Franz (WF) 則
Franz & Wiedemann, Annalen der Physik (1853)
マグノンWiedemann-Franz則
KN et al., PRB (2015)
Josephson効果
Josephson, Phys. Lett. (1962)
マグノンJosephson効果
KN et al., PRB (2014)
量子Hall効果
Klitzing et al., PRL (1980)
TKNN, PRL (1982) / Kohmoto, Ann. Phys. (1985)
マグノン``量子’’Hall効果
KN et al., PRB (2017)
強磁性絶縁体
トポロジカル絶縁体
Kane & Mele, PRL (2005, 2005).
Bernevig & Zhang, PRL (2006).
マグノントポロジカル絶縁体
KN et al., PRB (2017), PRL (2019)
反強磁性絶縁体
マグノン光誘起トポロジカル絶縁体
KN et al., PRB (2019)
電流雑音
Blanter and Buttiker, Phys. Rep. (2000): Review
マグノン流雑音
KN et al., PRB (2019)
KN et al., PRB (2019)
KN et al., PRB (2018)
Establish magnon counterparts !!
量子Hall効果
Klitzing et al., PRL (1980)
トポロジカル絶縁体
Kane & Mele, PRL (2005, 2005).
Bernevig & Zhang, PRL (2006).
トポロジカル物性
電子系
Fermion
非磁性不純物
不安定: 非磁性不純物 無:時間反転対称性
安定: トポロジカル保護機能 有:時間反転対称性
無:時間反転対称性
有:時間反転対称性強磁性絶縁体反
強磁性絶縁体
(巨視的磁化: 無 )
(巨視的磁化: 有 )
マグノン
Boson
(低エネルギーで有効的に回復)
鍵: 幾何学的位相
非磁性不純物
トポロジカル物性
KN et al., PRB (2017)
幾何学的位相
Aharonov-Casher位相
電気𝑒×磁場
𝜇B
磁気𝜇B×電場
𝑒
位相 位相
電子 マグノン
Aharonov-Bohm位相
Landau量子化:マグノン
Aharonov-Casher位相
𝜇B
磁気𝜇B×電場
位相
マグノン
Magnon Hamiltonian inAC effect:
AC vector potential:
Cyclotronmotion:
Landau energy level:
Cyclotronmotion frequency:
TODAY’S GOAL
``交流’’レーザー電場
KN, Kim, and Takayoshi,Phys. Rev. B (2019):反強磁性絶縁体
``直流’’外部電場
KN et al., Phys. Rev. B (2017): 強磁性絶縁体
KN et al., Phys. Rev. B (2017):反強磁性絶縁体
Kim, KN et al., Phys. Rev. Lett. (2019): フェリ磁性体
平衡系:マグノントポロジカル絶縁体
非平衡系:レーザー誘起マグノントポロジカル絶縁体
入力: ac電場(直線偏光・円偏光)
結合: 電場 𝑬(𝑡) × スピン𝝁B
機構: 時間周期的Aharonov-Casher位相
解析: Floquet理論(高周波展開)
量子光学:レーザー技術の発展
GOAL: トポロジカル物性を光デザイン・レーザー制御
acレーザー電場 円偏光:右巻き 円偏光:左巻き
時間反転対称性
直線偏光
有 無 無
エッジ状態
熱Hall効果
スピンNernst効果
Helical ?
?
?
?
?
?
反強磁性絶縁体
無
有
dc: Helical
熱Hall流 熱Hall流
Chiralエッジ:右回り
(a) 円偏光:右巻き (b) 円偏光:左巻き
Chiralエッジ:左回り
円偏光:Chiral エッジ
ス
ピ
ン
ホ
ー
ル
流
:
0
(zero)
温度勾配
熱
ホ
ー
ル
流
𝜇B
反強磁性絶縁体
トポロジカル不変量
円偏光:Chiral エッジ
−𝜇B
熱Hall効果
左巻き
熱
ホ
ー
ル
流
ス
ピ
ン
ホ
ー
ル
流
:
0
(zero)
円偏光:Chiral エッジ
熱Hall効果
反強磁性絶縁体
トポロジカル不変量
温度勾配
−𝜇B
𝜇B
右巻き
ス
ピ
ン
ホ
ー
ル
流
熱
ホ
ー
ル
流
:
0
(zero)
スピンNernst効果
𝜇B
−𝜇B
直線偏光:Helical エッジ
反強磁性絶縁体
トポロジカル不変量
温度勾配
量子光学:レーザー技術の発展
円偏光:右巻き 円偏光:左巻き
時間反転対称性
直線偏光
有 無 無
エッジ状態
熱Hall効果
スピンNernst効果
Helical Chiral Chiral
無
無 無
有 有
有
向き:
制御可能
反強磁性絶縁体
acレーザー電場
GOAL: トポロジカル物性を光デザイン・レーザー制御
dc: Helical
SUMMARY
トポロジカルスピン流物性:光デザイン・レーザー制御
スピントロニクス 量子光学
光学的マグノンスピントロニクス
トポロジカル物理
マグノン レーザー
エッジ状態 & Hall効果
レーザー誘起マグノントポロジカル絶縁体
レーザー誘起マグノントポロジカル絶縁体
KN, Kim, and Takayoshi, PRB 100, 014421 (2019)
Backup
Aharonov-Casher (AC) Effect on Magnons in AF
AC vector potential:
Magnon Hamiltonian:
Aharonov-Casher (AC) Effect on Magnons in AF
AC vector potential:
Magnon Hamiltonian:
Time-periodic E-field and the AC vector potential:
Linearly polarized laser Circularlypolarized laser
for
Effective FloquetHamiltonian:
High frequency expansion:
Geometric Phases
(Electrically) charged particle:
Magnetic vector potential 𝑨
Magnon = Magnetic dipole:
Aharonov-Bohm(AB) phase Aharonov-Casher (AC) phase
Electric vector potential:
Mignani, J. Phys. A (1991). Meier & Loss, PRL (2003).
Aharonov and Bohm, Phys. Rev. (1959) Aharonov and Casher, PRL (1984)
𝜵 × 𝑨 = 𝑩
Electric field coupling with magnons:
Hoogdalem et al., PRB (2013) [Katsura et al., PRL (2005)]:
DM int.  An analogue of artificial gauge field
 AC effect
Magnetic field couplingwith electrons:
Observation of AC effect on magnons:
Zhang et al. (Yale), PRL (2014)
Electric-Field couplingto magnons
𝜃AC =
𝑔𝜇B
ℏ𝑐2 𝑑𝒍 ∙ 𝑬 × 𝒆 𝒛 =
𝑔𝜇B
ℏ𝑐
𝑑𝒍 ∙ 𝑨m𝜃A𝐵 =
𝑒
ℏ𝑐
𝑑𝒍 ∙ 𝑨
𝜇 = 𝑔𝜇B 𝒆 𝑧
𝑨m ≡ 𝑬 × 𝒆 𝒛/𝑐
𝑒
𝜵 × 𝑨m = 𝜀𝒆 𝑧/𝑐 for 𝐸 = 𝜀(−𝑥, 0,0)
𝑒
𝑒↑
↓
Aharonov-Bohm effect
‘Possible’ (𝜎 = ±1 =↑, ↓)
by spin-orbit interaction
Murakami, NJP (2007)
𝑒 in 𝑩 𝜎 = 𝜎𝑩eff
‘Impossible’
in single layer
𝜎𝑒 in 𝑩 𝜎 = 𝑩eff
𝑒
𝑒−
Aharonov-Casher effect
‘Possible’
in single layered AF
KN et al., (2017)
𝜎𝜇B in E
𝜇B
𝜇B−
ℋ 𝜎 = 𝒑 + 𝑒𝑨 𝜎
2
Aharonov-Bohm effect
ℋ 𝜎 = 𝒑 + 𝜎𝑒𝑨 2
𝜵 × 𝑨 𝜎 = 𝑩 𝝈
𝜵 × 𝑨 = 𝑩eff
ℋ 𝜎 = 𝒑 + 𝜎𝑔𝜇B 𝑨m
2
𝑨m ≡ 𝑬 × 𝒆 𝒛
NOTE: Rough sketch with 𝑚 = 𝑐 = 1
電子スピン𝜇B(半導体)
マグノン𝜇B(絶縁体)
幾何学的位相:観測

More Related Content

Featured

How Race, Age and Gender Shape Attitudes Towards Mental Health
How Race, Age and Gender Shape Attitudes Towards Mental HealthHow Race, Age and Gender Shape Attitudes Towards Mental Health
How Race, Age and Gender Shape Attitudes Towards Mental Health
ThinkNow
 
Social Media Marketing Trends 2024 // The Global Indie Insights
Social Media Marketing Trends 2024 // The Global Indie InsightsSocial Media Marketing Trends 2024 // The Global Indie Insights
Social Media Marketing Trends 2024 // The Global Indie Insights
Kurio // The Social Media Age(ncy)
 

Featured (20)

2024 State of Marketing Report – by Hubspot
2024 State of Marketing Report – by Hubspot2024 State of Marketing Report – by Hubspot
2024 State of Marketing Report – by Hubspot
 
Everything You Need To Know About ChatGPT
Everything You Need To Know About ChatGPTEverything You Need To Know About ChatGPT
Everything You Need To Know About ChatGPT
 
Product Design Trends in 2024 | Teenage Engineerings
Product Design Trends in 2024 | Teenage EngineeringsProduct Design Trends in 2024 | Teenage Engineerings
Product Design Trends in 2024 | Teenage Engineerings
 
How Race, Age and Gender Shape Attitudes Towards Mental Health
How Race, Age and Gender Shape Attitudes Towards Mental HealthHow Race, Age and Gender Shape Attitudes Towards Mental Health
How Race, Age and Gender Shape Attitudes Towards Mental Health
 
AI Trends in Creative Operations 2024 by Artwork Flow.pdf
AI Trends in Creative Operations 2024 by Artwork Flow.pdfAI Trends in Creative Operations 2024 by Artwork Flow.pdf
AI Trends in Creative Operations 2024 by Artwork Flow.pdf
 
Skeleton Culture Code
Skeleton Culture CodeSkeleton Culture Code
Skeleton Culture Code
 
PEPSICO Presentation to CAGNY Conference Feb 2024
PEPSICO Presentation to CAGNY Conference Feb 2024PEPSICO Presentation to CAGNY Conference Feb 2024
PEPSICO Presentation to CAGNY Conference Feb 2024
 
Content Methodology: A Best Practices Report (Webinar)
Content Methodology: A Best Practices Report (Webinar)Content Methodology: A Best Practices Report (Webinar)
Content Methodology: A Best Practices Report (Webinar)
 
How to Prepare For a Successful Job Search for 2024
How to Prepare For a Successful Job Search for 2024How to Prepare For a Successful Job Search for 2024
How to Prepare For a Successful Job Search for 2024
 
Social Media Marketing Trends 2024 // The Global Indie Insights
Social Media Marketing Trends 2024 // The Global Indie InsightsSocial Media Marketing Trends 2024 // The Global Indie Insights
Social Media Marketing Trends 2024 // The Global Indie Insights
 
Trends In Paid Search: Navigating The Digital Landscape In 2024
Trends In Paid Search: Navigating The Digital Landscape In 2024Trends In Paid Search: Navigating The Digital Landscape In 2024
Trends In Paid Search: Navigating The Digital Landscape In 2024
 
5 Public speaking tips from TED - Visualized summary
5 Public speaking tips from TED - Visualized summary5 Public speaking tips from TED - Visualized summary
5 Public speaking tips from TED - Visualized summary
 
ChatGPT and the Future of Work - Clark Boyd
ChatGPT and the Future of Work - Clark Boyd ChatGPT and the Future of Work - Clark Boyd
ChatGPT and the Future of Work - Clark Boyd
 
Getting into the tech field. what next
Getting into the tech field. what next Getting into the tech field. what next
Getting into the tech field. what next
 
Google's Just Not That Into You: Understanding Core Updates & Search Intent
Google's Just Not That Into You: Understanding Core Updates & Search IntentGoogle's Just Not That Into You: Understanding Core Updates & Search Intent
Google's Just Not That Into You: Understanding Core Updates & Search Intent
 
How to have difficult conversations
How to have difficult conversations How to have difficult conversations
How to have difficult conversations
 
Introduction to Data Science
Introduction to Data ScienceIntroduction to Data Science
Introduction to Data Science
 
Time Management & Productivity - Best Practices
Time Management & Productivity -  Best PracticesTime Management & Productivity -  Best Practices
Time Management & Productivity - Best Practices
 
The six step guide to practical project management
The six step guide to practical project managementThe six step guide to practical project management
The six step guide to practical project management
 
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
 

レーザー誘起マグノントポロジカル絶縁体