Spin Chiral Anisotropy of Diamagnetic Chiral Mesostructured In₂O₃ Films

Spin chiral anisotropy (SChA) refers to the occurrence of different spin polarization in antipodal chiral structures. Herein, we report the SChA in diamagnetic chiral mesostructured In₂O₃ films (CMIFs) with manifestation of chirality-dependent magnetic circular dichroism (MCD) signals. CMIFs were grown on fluorine-doped tin dioxide conductive glass (FTO) substrates synthesized via a hydrothermal route, using malic acid as symmetry-breaking agents. Two levels of chirality have been identified in CMIFs: primary nanoflakes with atomically twisted crystal lattices and secondary helical stacking of the nanoflakes. CMIFs exhibit chirality-dependent asymmetric MCD signals due to the different interaction of chirality-induced effective magnetic field and external magnetic field, which distinguish from the commonly observed external magnetic field-dependent symmetric MCD signals. These findings provide insights into spin manipulation of spin-paired diamagnets.