Magnetic phase diagrams and large magnetocaloric effects of the two-dimensional antiferromagnetic triangular lattice of Gd$^{3+}$ ions in KBaGd(BO$_3$)$_2$

Bibliographic Details
Title: Magnetic phase diagrams and large magnetocaloric effects of the two-dimensional antiferromagnetic triangular lattice of Gd$^{3+}$ ions in KBaGd(BO$_3$)$_2$
Authors: Song, Z. M., Zhao, N., Ge, H., Li, T. T., Yang, J., Wang, L., Fu, Y., Zhang, Y. Z., Wang, S. M., Mei, J. W., He, H., Guo, S., Wu, L. S., Sheng, J. M.
Source: Physical Review B 107, 125126 (2023)
Publication Year: 2023
Collection: Condensed Matter
Subject Terms: Condensed Matter - Strongly Correlated Electrons
More Details: We report a detailed study of the magnetic properties of KBaGd(BO$_3$)$_2$, in which magnetic Gd$^{3+}$ ($S=7/2$) ions form into two-dimensional triangular layers. Magnetization, specific heat and magnetocaloric effect (MCE) measurements have been performed on KBaGd(BO$_3$)$_2$ single crystals. The results show that a long-range antiferromagnetic state is established below $T_{\rm N}=0.24$ K. In zero fields, only about half of the full entropy is released at $T_{\rm N}$, indicating that not all the magnetic moments are frozen below the ordering temperature, as expected from the geometrical frustration of the triangular spin lattice. Further studies under external fields were performed down to 50 mK, and the magnetic phase diagrams are established with magnetic fields applied both within and perpendicular to the triangular plane. KBaGd(BO$_3$)$_2$ serves as an example of a two-dimensional triangular lattice with large spin values ($S=7/2$) and can be directly compared with the iso-structure KBaR(BO$_3$)$_2$ (R = Dy-Yb) family of doublet ground states, which exhibit effective spins of $S=1/2$.
Comment: 8 pages, 5 figures
Document Type: Working Paper
DOI: 10.1103/PhysRevB.107.125126
Access URL: http://arxiv.org/abs/2303.10584
Accession Number: edsarx.2303.10584
Database: arXiv
More Details
DOI:10.1103/PhysRevB.107.125126