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Summary The photomagnetic effect is known to be related only to transition metal atoms with empty orbitals and spin-state changes. In general, noble metals with high electron density cannot be used as photomagnetic materials because of the absence of spin polarization. However, here, we found that photomagnetic-chiral anisotropy (PM-ChA) was generated in chiral nanostructured Au films (CNAFs), and opposite photomagnetic fields (PMFs) were created in the antipodal CNAFs under unpolarized irradiation. The PM-ChA was speculated to arise from directional alignment of opposite spins polarized by the asymmetric spin-orbit coupling due to the opposite effective magnetic fields induced by electron motion in the antipodal helical structure. PM-ChA can be applied in enantiomeric quantification, probably because of the spin polarization coupling between CNAFs and enantiomers. PM-ChA of noble metals generated by directional spin control in helical nanostructures could provide new strategies in quantum technology and theories in magnetophysics.

Summary The enantiomeric excess phenomenon in spontaneous chiral symmetry breaking (SCSB) is a crucial issue in the origin of homochirality in nature, whereas chiral inorganic compounds have long been reckoned as racemates. Here, we report the SCSB in the self-assembly of cadmium chalcogenide nanorods, leading to chiral biases away from the racemate. In the presence of achiral organics, helical CdSe@CdS nanorods (HCCNs) with unidirectionally rotated crystal lattices along the rod axis were stochastically formed on the epitaxial interface of the {111}cub/{0001}hex planes. The stability of helical dislocation structures, as supported by a theoretical analysis of their binding energies, suggested the possibility of the emergence of helical structures in an achiral environment. Hierarchical chiral films induced by simple solvent evaporation self-assembly of HCCNs exhibited spontaneous enantiomeric excess between batches, which was speculated to be originated from the enantiomeric excess seed assembly that induce one-handedness dominated system based on the majority rules.