A pulsed field magnet is a strong
electromagnet
An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil. A current through the wire creates a magnetic field which is concentrated in the ...
which is powered by a brief pulse of
electric current
An electric current is a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space. It is measured as the net rate of flow of electric charge through a surface or into a control volume. The moving pa ...
through its windings rather than a continuous current, producing a brief but strong pulse of
magnetic field
A magnetic field is a vector field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to ...
. Pulsed field magnets are used in research in fields such as
materials science to study the effect of strong magnetic fields, since they can produce stronger fields than continuous magnets. The maximum field strength that continuously-powered high-field electromagnets can produce is limited by the enormous
waste heat
Waste heat is heat that is produced by a machine, or other process that uses energy, as a byproduct of doing work. All such processes give off some waste heat as a fundamental result of the laws of thermodynamics. Waste heat has lower utility ...
generated in the windings by the large currents required. Therefore by applying brief pulses of current, with time between the pulses to allow the heat to dissipate, stronger currents can be used and thus stronger magnetic fields can be generated. The magnetic field produced by pulsed field magnets can reach between 50 and 100
T, and lasts several tens of milliseconds.
References
*{{cite journal , last1 = Webb , first1 = A.G. , year = 2013 , title = Radiofrequency microcoils for magnetic resonance imaging and spectroscopy , journal = Journal of Magnetic Resonance , volume = 229 , pages = 55–66 , doi = 10.1016/j.jmr.2012.10.004 , pmid=23142002, bibcode = 2013JMagR.229...55W
*Bernd Ctortecka
High-field NMR in pulsed magnets Max-Planck Innovation.
Electromagnetic coils
Nuclear magnetic resonance