Topological Aspect of Magnetic Structures in Paramagnetic Liquid Crystal

Abstract

Liquid-crystalline (LC) nitroxide radicals (NRs) with spin 1/2, localized in each mesogen core, exhibit anisotropic paramagnetic susceptibility in their LC phases. It is unclear whether the macroscopic magnetic structures of LC materials depend on the molecular orientational structures in the LC phases. Here, we report the persistence diagram of the macroscopic magnetic structures of an LC-NR on a ferromagnetic iron film in an image taken using photoemission electron microscopy. Furthermore, we discuss the topological aspect of the magnetic structures in the LC-NR by comparing the persistence diagram with that of the molecular orientational structures in a polarized optical micrograph of the same sample.