Ferromagnetism in Mn doped 3C-SiC: A variable temperature ESR study

Abstract

This paper discusses the effect of defects and role of charge carriers in setting up the long range magnetic order in Mn doped 3C-SiC. Using complementary experiments like temperature variation of Electron Spin Resonance (ESR) and DC magnetic susceptibility, the nature of magnetic interactions, spin dynamics and anisotropy have been investigated. The variation of ESR parameters such as, gvalue, peak to peak line width(Delta H-pp), spin density (N-s) and spin-spin relaxation time (T-2) as a function of temperature and dopant concentration confirms the presence of exchange interaction present in the system. The decrease in resonance field H-r as a function of temperature indicates the strengthening of internal field already existing in Mn doped 3C-SiC samples. This result confirms that defect induced magnetism could be enhanced by introducing holes in to the host wide band gap semiconductor.