Size and shape dependence study of magnetization reversal in magnetic antidot lattice arrays

• The periodic holes act as pinning center and make the domains to follow a zigzag path.
• Domain size for different magnetic antidot lattice arrays (MALs) has been studied.
• The relaxation behavior of MALs under constant magnetic field has been studied.

Magnetic Antidot Lattice (MAL) arrays of Co have been prepared in micron range using ultraviolet (UV) lithography technique with different shapes and sizes. Magnetization reversal in such MAL systems has been studied by magneto-optic Kerr effect (MOKE) based microscopy by varying the angle between the easy axis and the external magnetic field. The domain images evidence that the magnetization reversal along easy axis is highly dominated by nucleation of domains which is subsequently accompanied by domain wall motion. We have observed that with increase in active magnetic area domain size increases but on the contrary coercivity decreases. The presence of periodic holes turns the MALs magnetically hard when compared to similar thickness of continuous thin film. The magnetization relaxation along easy axis for the Co MAL at constant dc field fits very well with the exponential law of Fatuzzo–Labrune indicating domain nucleated dominant process.