Magneto-optical imaging of magnetic-domain pinning induced by chiral molecules

Chiral molecules have the potential for creating new magnetic devices by locally manipulating the magnetic properties of metallic surfaces. When chiral polypeptides chemisorb onto ferromagnets, they can induce magnetization locally by spin exchange interactions. However, direct imaging of surface magnetization changes induced by chiral molecules was not previously realized. Here, we use magneto-optical Kerr microscopy to image domains in thin films and show that chiral polypeptides strongly pin domains, increasing the coercive field locally. In our study, we also observe a rotation of the easy magnetic axis toward the out-of-plane, depending on the sample's domain size and the adsorption area. These findings show the potential of chiral molecules to control and manipulate magnetization and open new avenues for future research on the relationship between chirality and magnetization.

Automated summary

Chiral molecules have the potential to create new magnetic devices by locally manipulating the magnetic properties of metallic surfaces. By chemisorbing onto ferromagnets, chiral polypeptides can induce magnetization locally through spin exchange interactions. In this study, magneto-optical Kerr microscopy was used to directly image surface magnetization changes induced by chiral molecules, demonstrating their ability to control and manipulate magnetization.