Magnetic measurements based on magneto-optical Kerr effect on pnictide Ba(Fe1−x Cox)2As2/Fe thin film

We present characterization of Ba(Fe1−x Cox)2As2 thin film using a magneto-optical Kerr effect setup based on photoelastic modulation. The magneto optical technique has been used to analyse the thickness and the temperature dependence of the magnetic properties of epitaxial Ba(Fe1−x Cox)2As2/Fe thin films grown on MgO substrate. The first harmonics, of the reflected laser beam intensity from pnictide thin films is compared with a reference Fe thin film. The hysteretic loops of such samples at room temperature and at 5K are presented.