Light-induced topological superconductivity in transition metal dichalcogenide monolayers

• Published in: Physical Review B
• Main Authors: Julku, Aleksi, Kinnunen, Jami J., Camacho-Guardian, Arturo, Bruun, Georg M.
• Other Authors: Aarhus University, Department of Applied Physics, Universidad Nacional Autónoma de México, Aalto-yliopisto, Aalto University
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Physical Society 2022
• Subjects: Jenny; IPY
• Online Access: https://aaltodoc.aalto.fi/handle/123456789/117802; https://doi.org/10.1103/PhysRevB.106.134510

Funding Information: We acknowledge very useful discussions with Ataç İmamoğlu. A.J. acknowledges financial support from the Jenny and Antti Wihuri Foundation. The calculations presented above were performed using computer resources within the Aalto University School of Science “Science-IT” project. This work has been supported by the Danish National Research Foundation through the Center of Excellence “CCQ” (Grant Agreement No. DNRF156). Publisher Copyright: © 2022 American Physical Society. 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. Peer reviewed