Light-induced topological superconductivity in transition metal dichalcogenide monolayers

Monolayer transition metal dichalcogenides (TMDs) host deeply bound excitons interacting with itinerant electrons, and as such they represent an exciting new quantum many-body Bose-Fermi mixture. Here, we demonstrate that electrons interacting with a Bose-Einstein condensate (BEC) of exciton-polarit...

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Bibliographic Details
Published in:Physical Review B
Main Authors: Julku, Aleksi, Kinnunen, Jami J., Camacho-Guardian, Arturo, Bruun, Georg M.
Format: Article in Journal/Newspaper
Language:English
Published: 2022
Subjects:
IPY
Online Access:https://pure.au.dk/portal/en/publications/4e4b81fb-098f-4810-b639-e4140b13cc12
https://doi.org/10.1103/PhysRevB.106.134510
http://www.scopus.com/inward/record.url?scp=85140715725&partnerID=8YFLogxK
https://arxiv.org/pdf/2204.12229.pdf
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Summary:Monolayer transition metal dichalcogenides (TMDs) host deeply bound excitons interacting with itinerant electrons, and as such they represent an exciting new quantum many-body Bose-Fermi mixture. Here, we demonstrate that electrons interacting with a Bose-Einstein condensate (BEC) of exciton-polaritons can realize a two-dimensional topological px+ipy superconductor. Using strong coupling Eliashberg theory, we show that this is caused by an attractive interaction mediated by the BEC, which overcompensates the repulsive Coulomb interaction between the electrons. The hybrid light-matter nature of the BEC is crucial for achieving this, since it can be used to reduce retardation effects and increase the mediated interaction in regimes important for pairing. We finally show how the great flexibility of TMDs allows one to tune the critical temperature of the topological superconducting phase to be within experimental reach.