Quantum mechanics

STRIPS

Magnetic field

Engineering

Magnetization

Ellipsoid

Materials science

Classical mechanics

Demagnetizing field

Transverse plane

Physics

Magnetic moment

Cuboid

Mathematics

Astronomy

Superconductivity

Condensed matter physics

Electromagnetic induction

Geometry

Diamagnetism

Composite material

Moment (physics)

Structural engineering

Electromagnetic coil

Mechanics

Electrical conductor

Physical Review Applied

Effective demagnetizing factors that connect the sample magnetic moment with the applied magnetic field are calculated numerically for perfectly diamagnetic samples of various non-ellipsoidal shapes. The procedure is based on calculating total magnetic moment by integrating the magnetic induction obtained from a full three dimensional solution of the Maxwell equations using adaptive mesh. The results are relevant for superconductors (and conductors in AC fields) when the London penetration depth (or the skin depth) is much smaller than the sample size. Simple but reasonably accurate approximate formulas are given for practical shapes including rectangular cuboids, finite cylinders in axial and transverse field as well as infinite rectangular and elliptical cross-section strips.

Effective Demagnetizing Factors of Diamagnetic Samples of Various Shapes