Evolution of superconductivity in twisted graphene multilayers

• 成果类型: Article
• 署名作者: Long, Min; Jimeno-Pozo, Alejandro; Sainz-Cruz, Hector; Pantaleon, Pierre A.; Guinea, Francisco
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11134
• DOI: 10.1073/pnas.2405259121
• 发表日期: 2024-08-06
• 关键词: unconventional superconductivity; correlated states; bilayer graphene

摘要

The group of moir & eacute; graphene superconductors keeps growing, and by now it contains twisted graphene multilayers as well as untwisted stacks. We analyze here the contribution of long-range charge fluctuations in the superconductivity of twisted double bilayers and helical trilayers, and compare the results to twisted bilayer graphene. A diagrammatic approach which depends on a few, well-known parameters is used. We find that the critical temperature and the order parameter differ significantly between twisted double bilayers and helical trilayers on one hand, and twisted bilayer graphene on the other. This trend, consistent with experiments, can be associated with the role played by moir & eacute; Umklapp processes in the different systems.