2023/10/18 by Muhammad Akram, Akram, Muhammad, Jesse Kapeghian +9 · 3 citations
Materials Science · Physics and Astronomy · #2D Materials and Applications #Advanced Condensed Matter Physics #Antiferromagnetism #Condensed matter physics #Geometry #Ground state #Magnetism #Materials science #Monolayer #Nanotechnology #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Stacking #Superlattice #Zigzag #van der Waals force
paper · pdf · doi:10.48550/arxiv.2310.12211
published in arXiv (Cornell University) (Cornell University)
openalex publication_date 2023/10/18 · openalex created_date 2023/10/21 · openalex updated_date 2026/07/28
Twisted heterostructures of van der Waals materials have received much attention for their many remarkable properties. Here, we present a comprehensive theory of the long-range ordered magnetic phases of twisted bilayer α-RuCl3 via a combination of first-principles calculations and atomistic simulations. While a monolayer exhibits zigzag antiferromagnetic order with three possible ordering wave vectors, a rich phase diagram is obtained for moiré superlattices as a function of interlayer exchange and twist angle. For large twist angles, each layer spontaneously picks a single zigzag ordering wave vector, whereas, for small twist angles, the ground state involves a combination of all three wave vectors in a complex hexagonal domain structure. This multi-domain order minimizes the interlayer energy while enduring the energy cost due to the domain wall formation. Our results indicate that magnetic frustration due to stacking-dependent interlayer exchange in moiré superlattices can be used to tune the magnetic ground state and enhance quantum fluctuations in α-RuCl3.