Abstract | Moiré crystals support flat bands with significant electron correlation effects, providing a novel platform for realizing unconventional superconductivity. In this talk, I will discuss our recent theoretical work on unconventional superconducting phenomena in moiré crystals. In the first part of the talk, I will present our study of unconventional Josephson effects mediated by valley-polarized states in MATBG Josephson junctions. We show that valley polarization, combined with trigonal warping effects, can lead to φ₀-Josephson effects and Josephson diode behavior, even in the absence of spin-orbit coupling. I will also introduce our recent proposal for realizing Majorana fermions using Josephson junctions in low-dimensional materials. Finally, I will discuss the orbital FFLO pairing state in moiré homobilayer transition metal dichalcogenides. References: [1]Ying-Ming Xie, Dmitri K Efetov, K. T. Law, Physical Review Research 5, 023029 (2023). [2] Ying-Ming Xie, ´Etienne Lantagne-Hurtubise, Andrea F. Young, Stevan Nadj-Perge, and Jason Alicea, Phys. Rev. Lett. 131, 146601 (2023) [3] Ying-Ming Xie, K. T. Law, Orbital Fulde-Ferrell pairing state in moir´e Ising superconductors, Phys. Rev. Lett. 131, 016001 (2023) |
