A double axis X-ray diffractometer for magnetostriction measurements

Abstract

The device described incorporates a helium gas flow cryostat for measurements down to 4.2K. By setting the crystal on the flank of the rocking curve, the change in lattice parameter is deduced from the change in intensity of the diffracted beam during rotation of a magnetic field of up to 1.25 T flux density. Even in crystals with rocking curves 30 seconds of arc in width, a strain sensitivity of about 10^-6 can be achieved. The feasibility of the technique has been assessed by measuring the magnetostriction of a substituted rare earth iron garnet film.