Common permanent magnets with multi poles magnetizations are 4 poles, 6 poles, 8 poles or more which depend on the dimensions and the application of the magnets.
A Halbach Array is a special arrangement of permanent magnets that augments the magnetic field on one side of the array while reducing the field to near zero on the other side. This was achieved by having a spatially rotating of magnetization.
It is convenient to manufacture multi-pole magnetized, excellent performance consistency and uniformity, are widely used in all kinds of micro motors and sensor systems