Direct measurement of preisach diagram from microhystersis loops at various delay times

We report a direct and practical method of characterizing interaction field utilizing microhysteresis loops within an element area at submicrometer scale (0.34 /spl mu/m/spl times/0.34 /spl mu/m), on perpendicular anisotropic magnetic thin film material. The magnetization reversal behaviors at submicrometer scale were observed with various applied delay times under a series of applied magnetic fields. Our studies provide evidence of the asymmetrical behavior of microhysterons due to the interaction field of nearby magnetic elements.