中国物理B ›› 2023, Vol. 32 ›› Issue (1): 17504-017504.doi: 10.1088/1674-1056/ac8f39
Magnetocaloric properties and Griffiths phase of ferrimagnetic cobaltite CaBaCo4O7
Tina Raoufi1,2, Jincheng He(何金城)1,2, Binbin Wang(王彬彬)1,2, Enke Liu(刘恩克)1,2, and Young Sun(孙阳)1,3,†
- 1 Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
3 Center of Quantum Materials and Devices, Chongqing University, Chongqing 401331, China
Magnetocaloric properties and Griffiths phase of ferrimagnetic cobaltite CaBaCo4O7
Tina Raoufi1,2, Jincheng He(何金城)1,2, Binbin Wang(王彬彬)1,2, Enke Liu(刘恩克)1,2, and Young Sun(孙阳)1,3,†
- 1 Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
2 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
3 Center of Quantum Materials and Devices, Chongqing University, Chongqing 401331, China
摘要： We present a study on the magnetocaloric properties of a CaBaCo$_{4}$O$_{7}$ polycrystalline cobaltite along with research on the nature of magnetic phase transition. The magnetization as a function of temperature identifies the ferrimagnetic to paramagnetic transition at a Curie temperature of 60 K. Moreover, a Griffiths-like phase is confirmed in a temperature range above $T_{\rm C}$. The compound undergoes a crossover from the first to second-order ferrimagnetic transformation, as evidenced by the Arrott plots, scaling of the universal entropy curve, and field-dependent magnetic entropy change. The maximum of entropy change is 3 J/kg$\cdot$K for $\Delta H = 7$ T at ${T}_{\rm C}$, and a broadening of the entropy peak with increasing magnetic field indicates a field-induced transition above $T_{\rm C}$. The analysis of the magnetic entropy change using the Landau theory reveals the second-order phase transition and indicates that the magnetocaloric properties of CaBaCo$_{4}$O$_{7}$ are dominated by the magnetoelastic coupling and electron interaction. The corresponding values of refrigerant capacity and relative cooling power are estimated to be 33 J/kg and 42 J/kg, respectively.
中图分类号: (Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.))
- 75.40.Cx