Magnetic Domains of Single-Domain Particles of SmCo₅ Observed by the Colloid-SEM Method

Magnetic domains of ball-milled small particles of the SmCo 5 phase below several microns in size have been observed by the colloid-SEM (scanning electron microscope) method, a modified Bitter method. Domains on the c plane of single-domain particles were found when the particle size decreased. Measurements show that sizes of two single-domain particles are 2.2 and 1.6 µm. These values are discussed with the theoretical critical sizes for the single-domain particles of SmCo 5 .