X-ray diffraction and magnetometric studies of Fe/Gd superlattices with Gd layer thicknesses from 96 to 351 Å, significantly exceeding the thickness of Fe layers (35 Å), as well as Fe/GdH superlattices subjected to hydrogenation, have been performed. After hydrogenation of the Fe/Gd superlattices, a mixture of crystalline phases GdH and GdH is formed in the GdH layers. It has been established that due to the effect of the proximity of the Fe layers during hydrogenation, a special magnetic order is formed in the GdH layers: the orientation of the magnetic moments in the temperature range T = 100–300 K does not depend on temperature, and the moments themselves are ordered antiparallel to the magnetic moments of the Fe layers. It can be assumed that the magnitude of the magnetic moments in the center of the GdH layers decreases with increasing temperature. The Curie temperature estimate for them gives values T = 100–120 K. The magnetic moments in the interface regions of the Gd and GdH layers differ by a factor of 2-3. Estimates show that the magnitudes of the magnetic moments in the GdH layers are 1-2 orders of magnitude higher than those in bulk and thin-film gadolinium hydride samples.
Likhachev et al. (Wed,) studied this question.