A holographic measurement of magnetostriction

Abstract

The field dependent behavior of the magnetostriction in polycrystalline TbPe2 has been measured by the techniques of real time holographic interferometry, at fields up to 12 KOe. The external field behavior of the magneto striction is determined for samples of cylindrical and ellipsoidal shape, and the internal field dependence is determined for the ellipsoidal sample. A theory is developed for the analysis of real time effects, by a simple extension of double exposure methods The theory leads to an expression for the shape and position of the holographically generated interference fringes associated with object deformation. Using this expression, the shape and position of the interference fringes for various different object shapes and deformations are generated by a computerized method, and compared to those observed in the real time mode. There is good agreement between theory and experiment.