Imperial College London
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ProfessorJohannesLischner

Faculty of Engineering, Department of Materials

Professor of Theory and Simulation of Materials
 
 
 
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Contact

 

+44 (0)20 7594 9949j.lischner

 
 
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Location

 

342Bessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Maity:2022:10.1103/PhysRevB.105.L041408,
author = {Maity, I and Mostofi, AA and Lischner, J},
doi = {10.1103/PhysRevB.105.L041408},
journal = {Physical Review B: Condensed Matter and Materials Physics},
pages = {1--6},
title = {Chiral valley phonons and flat phonon bands in moire materials},
url = {http://dx.doi.org/10.1103/PhysRevB.105.L041408},
volume = {105},
year = {2022}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We investigate the chirality of phonon modes in twisted bilayer WSe2 and demonstrate distinct chiral behavior of the K/K′ valley phonons for twist angles close to 0 and close to 60. In particular, multiple chiral nondegenerate K/K′ valley phonons are found for twist angles near 60 whereas no nondegenerate chiral modes are found for twist angles close to 0. Moreover, we discover two sets of emergent chiral valley modes that originate from an inversion symmetry breaking at the moiré scale and find similar modes in moiré patterns of strain-engineered bilayers WSe2 and MoSe2/WSe2 heterostructures. At the energy gap between acoustic and optical modes, the formation of flat phonon bands for a broad range of twist angles is observed in twisted bilayer WSe2. Our findings are relevant for understanding electron-phonon and exciton-phonon scattering in moiré materials and also for the design of phononic analogues of flat band electrons.
AU  - Maity,I
AU  - Mostofi,AA
AU  - Lischner,J
DO  - 10.1103/PhysRevB.105.L041408
EP  - 6
PY  - 2022///
SN  - 1098-0121
SP  - 1
TI  - Chiral valley phonons and flat phonon bands in moire materials
T2  - Physical Review B: Condensed Matter and Materials Physics
UR  - http://dx.doi.org/10.1103/PhysRevB.105.L041408
UR  - https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000752506000005&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
UR  - https://journals.aps.org/prb/abstract/10.1103/PhysRevB.105.L041408
UR  - http://hdl.handle.net/10044/1/104774
VL  - 105
ER  -
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