Axisymmetric electropermanent magnets

A method for switching a magnetic field external to a magnet assembly comprising:

• providing the magnet assembly, wherein the magnet assembly comprises:
• at least one fixed permanent magnet having a first direction of magnetization from a south end of the at least one fixed permanent magnet to a north end of the at least one fixed permanent magnet, wherein the first direction of magnetization is in a first direction;
• at least one switching permanent magnet having a second direction of magnetization from a south end of the at least one switching permanent magnet to a north end of the at least one switching permanent magnet, and
• wherein one or more fixed permanent magnets of the at least one fixed permanent magnet are positioned at least partially within a corresponding one or more bores through a first switching permanent magnet of the at least one switching permanent magnet or one or more switchable permanent magnets of the at least one switching permanent magnet are positioned at least partially within a corresponding one or more bores through a first fixed permanent magnet of the at least one fixed permanent magnet,
• when the second direction of magnetization of the at least one switching permanent magnet is in the first direction, switching the second direction of magnetization from the first direction to a second direction by positioning an on-to-off switching magnetic field with respect to the magnet assembly for a first period of time, where the second direction is opposite to the first direction, wherein the positioning of the on-to-off switching magnetic field does not switch the first direction of magnetization the at least one fixed permanent magnet;
• and
• when the second direction of magnetization of the at least one switching permanent magnet is in the second direction, switching the second direction of magnetization from the second direction to the first direction by positioning an off-to-on switching magnetic field with respect to the magnet assembly for a second period of time, where the off-to-on switching magnetic field is in an opposite direction to the on-to-off switching magnetic field, wherein the positioning of the off-to-on switching magnetic field does not switch the first direction of magnetization of the at least one fixed permanent magnet.