Investigation of magnetic order and spin dynamics in Mn doped 3C-SiC

As SiC is a technological important material which is being used for a wide variety of device applications that can work under harsh environment, inducing magnetic order in this material without altering its other physical properties can lead to the development of multifunctional magneto electronics devices, that can operate under extreme conditions such as high power, high temperature and high radiation. We have synthesized Mn doped 3C-SiC (Mn-1%, 3% and 5%) by thermal plasma technique and investigated the nature of magnetic interactions, anisotropy and its temperature dependence using DC, AC magnetometry and magnetic resonance studies. The samples exhibit ferromagnetic transition with high Curie temperature above 780 K. Isothermal DC magnetic measurement shows Hysteresis with coercivity value of 240 Oe at 5 K which reduces to 40 Oe at room temperature. There is spin reorientation below 50 K. The magnetic anisotropy decreases with increase in temperature. Detailed analysis of DC and AC magnetization measurements and temperature dependence of electron paramagnetic resonance spectra indicates that the long range magnetic order may be due to interaction among Mn2+ ions mediated by holes.