Magnetism

Abstract

N the preceding volumes of Reports on Progress in Physics some attention has been paid to the theoretical aspects of modem magnetism, and with the appear-I ance of the articles by Sommerfeld and Bethe(') and the publication of &!agnetism and Matter(') many of the theoretical contributions of recent years have been conveniently summarized. There remains, however, a very large body of work of fundamental importance, mainly experimental, which will be surveyed as fully as possible in the present report. An indication of the amount of this work may be gained by consulting the list of some 211 references given in a review of research work in magnetism during 1933-34 compiled by S p o ~n e r ( ~) , although work on diaand paramagnetics has been generally excluded from this list. In the present report attention will be in the main confined to work carried out in the period 1930-3j, but, because this is an initial report and a report on magnetism will not be published annually, some latitude will be taken in the inclusion of material published outside this interval of time.The writer has obviously been forced to make a somewhat arbitrary selection of material, and some branches of the subject have perforce been omitted. For example, magneto-optics and galvanomagnetic phenomena are not discussed here, but these and other effects are well treated elsewhere.

Motion of an anisotropic crystal in a rotating magnetic field

“…(2) (Bates 1936) where 0 is the angle between H and the principal axis kl. I n general the object will tend to orient itself with the direction of highest susceptibility parallel to the field.…”