PURPOSE: To improve the precision of measurement of a magnetic domain width by arranging a bubble crystal of a sample in parallel with the magnetic pole face of a permanent magnet and moving the position, where the magnetic domain of the bubble crystal should be expanded into the shape of a parallel line, in the direction crossing the ridgeline of a corner part of the permanent magnet to expand surely the magnetic domain even if the diameter of the bubble is reduced.
CONSTITUTION: A spacer 6 is moved back and forth in the direction where a point 1a to be measured traverses a ridgeline P-Q of a corner part 5 between upper and lower magnetic pole faces 4n and 4s of a permanent magnet 4 and a side face 4a, namely, in the direction of an arrow a1. Then, the bubble domain at the point 1a of a bubble crystal 1 is expanded into the shape of a parallel line. A magnetic flux F near the edge part 5 is divided to components α in the direction parallel with the plane of the bubble crystal above it and components β in the direction vertical to this plane. Therefore, components α in the direction of the plane correspond to a DC magnetic field, and the bubble magnetic domain is expnded in the α direction, namely, in the direction vertical to the ridgeline P-Q. The bubble crystal 1 is moved on the edge part 5 in the direction vertical to it, but it is considered that the bubble crystal 1 is moved with minute oscillation, and components in the direction vertical to the crystal face act similarly to an AC magnetic field to move the bubble magnetic domain more easily.
| JPS56143586 | MAGNETIC BUBBLE STORAGE DEVICE |
UCHISHIBA HIDEMA
YAMAGUCHI KAZUYUKI
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