Photomagnetic-chiral anisotropy of chiral nanostructured gold films

Abstract

•PM-ChA was created by CNAFs under laser irradiation •The mechanism is attributed the directional alignment of specific spins •PM-ChA can be applied for universal enantiomeric discrimination •Enantiomeric discrimination is associated with selective spin polarization coupling 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. 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. Photomagnetic-chiral anisotropy of chiral nanostructured gold filmsLiu et al.ChemFebruary 10, 2022In Brief(Chem 8, 186–196, January 13, 2022) Full-Text PDF