Surface spin glass behavior in sol–gel derived La0.7Ca0.3MnO3nanotubes

Abstract

We report the fabrication of La_0.7Ca_0.3MnO₃nanotubes (LCMONTs) with a diameter of about 200 nm, by a modified sol–gel method utilizing nanochannel alumina templates. High resolution transmission electron microscopy confirmed that the obtained LCMONTs are made up of nanoparticles (8–12 nm), which are randomly aligned in the wall of the nanotubes. The strong irreversibility between zero field cooling (ZFC) and field cooling (FC) magnetization curves as well as a cusplike peak in the ZFC curve gives strong support for surface spin glass behavior.