We investigated the anisotropy of the magnetic and magnetocaloric properties of single-crystalline double-perovskite Tb2CoMnO6, which crystallizes in a monoclinic P21/n structure. Due to dissimilar magnetic anisotropy, the ferromagnetic order of the Co2+ and Mn4+ moments emerges along the c axis at TC=100K, and the larger Tb3+ moments align perpendicular to the c axis, below TTb=15K. The intricate temperature development of the metamagnetism along the c axis results in a large negative change in the magnetic entropy at low temperature. On the other hand, the larger but almost reversible magnetization, perpendicular to the c axis, results in a small and positive entropy change. This highly anisotropic magnetocaloric effect (MCE) leads to a giant rotational MCE, estimated to be 20.8J/kgK. Our findings, based on the magnetic anisotropy in Tb2CoMnO6, enrich fundamental and applied research on magnetic materials, considering the distinct magnetic characteristics of double perovskites.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) Grants No. NRF-2016R1C1B2013709, No. NRF-2017K2A9A2A08000278, No. 2017R1A5A1014862 (SRC program: vdWMRC center), and No. NRF-2018R1C1B6006859. J.Y.M. acknowledges tuition support from the Hyundai Motor Chung Mong-Koo Foundation.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics