| Arthur
von Hippel and Magnetism
John B. Goodenough
Abstract
This article examines the role that Arthur von Hippel played in magnetism
work in the 1950s. Von Hippel understood that the ferrimagnetic insulators
represented by the ferrospinels, magnetoplumbites, and ferrogarnets were
critical for the high-frequency technology that was being developed after
World War II. At the Laboratory for Insulation Research at MIT, he and
his students concentrated on the response of these materials to electric
and magnetic excitations over a wide frequency range that extended, with
gaps, from dc to the ultraviolet. For magnetic studies, he used microwave
frequencies to obtain resonance and relaxation data that could be interpreted
because the magnetic spins are relatively loosely coupled to their surroundings.
He supplemented these resonance studies with classical magnetometer, transport,
and x-ray diffraction measurements on single-crystal samples in order
to obtain fundamental information that would aid in the design of materials
for technical applications.
Keywords: Arthur von Hippel, magnetism. |
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