Multi-Axis (2-axis and 3-axis) Magnets
Multi-axis magnets provide variable magnetic field on two or three principal axes
and are particularly useful for orientation studies on a variety of samples.
The magnet is comprised of three independently controlled coil sets. A
solenoid coil produces the highest field along one axis. Two sets of split
coils produce the fields along the other two axis. By correctly energizing
the coils with the correct currents a combined vector field can be produced in a
given direction at a known magnitude. This allows the user to electronically
manipulate the field relative to the sample without the use of complex sample
rotation equipment or physically rotating the magnet position. Forces in such
magnets can be extremely high due to the interaction between each coil when they
are energized simultaneously. Care must be taken to stay within the factory
defined operating envelop or damaged to the magnet and the cryostat could
result. Coil configurations can be with the split coils surrounding the solenoid
or the split coils can be nested inside the bore of a large solenoid. Typical specifications
include high field up to 9T for the principal axis, 2.0/3.0 inch vertical clear
bore and 1T rotating vector using any combination of x, y and z-axis magnets.
Photo to left shows a 3-axis magnet with a compensated low field region on top
for operation with a dilution refrigerator.
The 3-axis magnet system provides a unique
way to rotate the magnetic field vector on the three principal axes and
this has proved useful in performing anisotropic studies on a variety of
materials. These magnet system have also been very useful in advancing
research in the areas of spin based physics. AMI provides magnet system
software for automatic sequencing of power supply currents and thus magnetic
fields that allow the user to specify and control the magnetic field
vector from a single computer screen. The interface allows the user to
enter the desired field vector of a 3-axis magnet in Cartesian,
cylindrical, or spherical coordinates. Cryogen Free systems and Optical
Access systems are available.