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Updated: May 16, 2025
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
Deteriorated Interlayer Coupling in Twisted Bilayer Cobaltites
Dongke Rong1,2, Xiuqi Chen1,2, Shengru Chen1,2,3
1Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Abstract:
A wealth of remarkable behaviors is observed at the interfaces between magnetic oxides due to the coexistence of Coulomb repulsion and interatomic exchange interactions. While previous research has focused on bonded oxide heterointerfaces, studies on magnetism in van der Waals interfaces remain rare. In this study, we stacked two freestanding cobaltites with precisely controlled twist angles. Scanning transmission electron microscopy revealed clear and ordered moiré patterns, which exhibit an inverse relationship with the twist angle. We observed that the Curie temperature in the twisted region is lower than that in the single-layer region and varies systematically with the twist angle. This phenomenon may be related to the weakening of the orbital hybridization between oxygen ions and transition metal ions in the unbonded interfaces. Our findings suggest a potential avenue for modulating magnetic interactions in correlated systems through twist, providing opportunities for the discovery of unknown quantum states.
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