Creating a Three-Dimensional Intrinsic Electric Dipole on Rotated CrI₃ Bilayers

New multiferroic platforms by sliding or rotation are being explored in two-dimensional (2D) materials [1,2,3]. Antiferromagnetically-coupled CrI₃ bilayers are one of the most studied magneto-electric multiferroic 2D materials [4]. Without considering magnetism, those bilayers possess a crystalline point of inversion, which can only be removed by antiparallel spin configuration between their two monolayers [4]. However, relative rotations between layers break the crystalline point of inversion, resulting in an inherent electric dipole moment <b>P</b>. Magnetoelectric couplings can be enhanced this way on a two-dimensional bilayer that is experimentally accessible [5].<br/><br/>This work was funded by MonArk NSF Quantum Foundry, supported by the National Science Foundation Q-AMASE-i program under NSF Award DMR-1906383. Calculations were performed on Cori at the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science user facility operated under contract No. DE-AC02-05CH1231, the Arkansas High-Performance Computing Center's Pinnacle supercomputer, and the Tempest Research Cluster at Montana State University.<br/><br/>References:<br/><br/>[1] Wu et. al. ACS Nano, <b>11</b>, 6382-6388, 2017.<br/>[2] Marmolejo-Tejada et al. Nano Lett. <b>22</b>, 19, 2022.<br/>[3] Junyi Ji et al. Phys. Rev. Lett. <b>130</b>, 146801, 2023.<br/>[4] Sun et al. Nature <b>572</b>, 497, 2019.<br/>[5] Poudel et al. Phys. Rev. B <b>107</b>, 195128, 2023.