Spin Chiral Anisotropy of Chiral Mesostructured Inorganic Materials with Different Intrinsic Magnetisms

Spin anisotropy breaking spin degeneracy is conventionally controlled by magnetic components. Spin chiral anisotropy (SChA) (i.e., chirality-dependent spin anisotropy) can be realized through the asymmetric spin-orbit coupling (SOC) between the chiral potential and spins in chiral materials without magnetic components, in which opposite spin polarization occurs in left- and right-handed srtructures. It is important to explore the SChA of chiral materials with special magnetic components for the further development of spintronics and potential applications. Among various chiral materials, chiral mesostructured inorganic materials (CMIMs) with various intrinsic magnetisms have recently emerged as promising and intriguing materials to address these issues due to their strong SOC at multiple chiral scales ranging from the subnanometer to micrometer, as well as diverse electronic states that can be excited by multiple stimuli, such as light, heat, electric fields, and magnetic fields. We have developed accessible technology for fabricating CMIMs and characterized the spin anisotropy-related responses based on their optical, electrical, and magnetic properties.In this Account, we provide a brief introduction to the synthesis progress and chiral mesostructures of CMIMs with intrinsic magnetism, including paramagnetism, antiferromagnetism, ferrimagnetism, and diamagnetism, especially the characterization of their SChA-related chiral responses based on the electron motions of transfer and transition. This Account covers the newly discovered SChA-related chiral responses and exploration of the influences of the intrinsic magnetisms on the SChA of CMIMs. These findings demonstrate that SChA-based electron transfer is rarely observed in CMIMs with poor conduction, but certain inorganic materials can exhibit SChA-based electron transfer after they are endowed with mesostructures.The paramagnetic CMIMs of Au and Au-Ag exhibit both SChA-based electron transfer and an SChA-related asymmetric electron transition. The antiferromagnetic CMIM of NiO uniquely shows SChA-based electron transfer, although it is a semiconductor. As a half-metal with 100% spin polarization at the Fermi level, the ferrimagnetic CMIM of Fe3O4 exhibits SChA-based electron transfer as a phenomenon of resistance chiral anisotropy (R-ChA). An SChA-based electron transition can be observed in the antiferromagnetic CMIMs of NiO and alpha-Fe2O3, and diamagnetic CMIMs of BiOBr and In2O3. In contrast, the ferrimagnetic CMIMs of Fe3O4 and gamma-Fe2O3 show external magnetic field-dependent spin anisotropic electron transitions. It is concluded that the competition between SChA and the external magnetic-field-based spin anisotropy determines which spin will be predominant. In the final section, the remaining challenges and opportunities for research on CMIMs and their SChA for advanced spintronics are highlighted. We hope that this Account will deepen the understanding of SChA in chiral materials with various intrinsic magnetism and that our insights will inspire innovative structural constructions and more possible spin-related functions of CMIMs in future research.