Room Temperature Ferromagnetic Semiconductor Rutile Th_(1-x)co_xo_(2-δ) Epitaxial Thin Films Grown By Sputtering Method

摘要

Room temperature (RT) ferromagnetic semiconductor rutile Ti_(1-x) Co_xO_(2-δ)(101) epitaxial thin films were grown on r-sapphire substrates by a dc sputtering method. Ferromagnetic magnetization, magnetic circular dichroism, and anomalous Hall effect were clearly observed at RT in sputter-grown films for the first time. The magnetization value is nearly as large as 3 _(μ_B)/Co that is consistent with the high spin state Co~(2+) in this compound recently established by spectroscopic methods. Consequently, its originally large magneto-optical response is further enhanced.