We report the detailed study of the magnetocaloric effect (MCE) in a dipolar-Heisenberg magnet LiGdF4 using magnetization measurements performed on a single crystal sample. Entropy variation on isothermal demagnetization from the magnetic field up to 3 T is determined in the temperature range 2-10 K for two principal directions of the applied field (parallel and perpendicular to the tetragonal c-axis of the crystal). The MCE is found to be highly anisotropic, with the cooling efficiency being up to twice higher at H∥c. The results are nicely interpreted in the frame of a conventional molecular field approach taking into account considerable anisotropy of the paramagnetic Curie-Weiss temperature. These results are compared to earlier studies of MCE in powder samples of LiGdF4 [T. Numazawa et al., AIP Conf. Proc. 850, 1579 (2006)] as well as with analogous data for other well known magnetocaloric materials. Our findings may open new possibilities to enhance the efficiency of magnetic refrigeration in the liquid helium-4 temperature range.
@article{arxiv.2307.06111,
title = {Strongly anisotropic magnetocaloric effect in a dipolar magnet LiGdF$_4$},
author = {G. Iu. Andreev and I. V. Romanova and O. A. Morozov and S. L. Korableva and R. G. Batulin and V. N. Glazkov and S. S. Sosin},
journal= {arXiv preprint arXiv:2307.06111},
year = {2023}
}