/
Week 11, Magnetic field, Haldane Model, Week 11, Magnetic field, Haldane Model,

Week 11, Magnetic field, Haldane Model, - PowerPoint Presentation

amber
amber . @amber
Follow
67 views
Uploaded On 2023-10-04

Week 11, Magnetic field, Haldane Model, - PPT Presentation

Chern number Gauge invariance Peierls substitution linear response Kubo formula integer quantum Hall effect Berry curvature Chern number TKNN formula Electron Hamiltonian in electromagnetic field ID: 1022651

haldane berry left curvature berry haldane curvature left model chern number formula vectors tknn electron neighbor space denoted arrows

Share:

Link:

Embed:

Download Presentation from below link

Download Presentation The PPT/PDF document "Week 11, Magnetic field, Haldane Model," is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.


Presentation Transcript

1. Week 11,Magnetic field, Haldane Model, Chern number Gauge invariance, Peierls substitution, linear response, Kubo formula, integer quantum Hall effect, Berry curvature, Chern number, TKNN formula

2. Electron Hamiltonian in electromagnetic field

3. Haldane model (1988)  AB

4. The Haldane model in k space    nearest neighbor vectors denoted by red arrows, next nearest neighbor vectors denoted by grey dotted arrows.   

5. Linear response theory for conductivity0

6. Apply Wick’s theorem to compute GJJ  

7. Back to real time t and then 

8. From contour  to retarded 

9. DC conductivity,   0

10. Berry phase/Berry curvature  20 1

11. Computing Berry curvature from eigenstates

12. Chern number, TKNN formula (1982)

13. Haldane modelTop left: real space and reciprocal space geometry.Left: band structure at fixed  and , as decreases from 0 passing the critical point, when , in (c).Top: Berry curvature for different (as in left figure (a), (b) and (d)).   

14. DC conductivity, taking the 0 limit differently

15. Other aspects of Berry phase physicsInterpretation/calculation of electro-polarization of ferroelectric materials Electron-phonon interaction in Born-Oppenheimer approximationElectron transport in adiabatic driven systemsBerry phases in periodic driven systems, Floquet theory, etc