Magnetic and magnetocaloric properties of CuMn₂O₄ and Mn₃O₄ composite system

Study of physical properties of a ferrimagnetic spinel Cu1.5Mn1.5O4: spin dynamics, magnetocaloric effect and critical behavior

“…This rapid increase corresponds to a rapid rearrangement of the Weiss domains in the direction of the applied magnetic eld. This conrms a characteristic of FIM materials 34. Above T C , a decrease of M(m 0 H) is observed with an almost linear behavior, which is typical for PM materials 34.…”

“…This conrms a characteristic of FIM materials 34. Above T C , a decrease of M(m 0 H) is observed with an almost linear behavior, which is typical for PM materials 34. Fig.3bdemonstrates the Arrott plots (H/M vs. M 2 ) for Cu 1.5 Mn 1.5 O 4 which are derived from the isothermal magnetizations.…”

“…This m the eff is very close to our m exp eff . The obtained values of T C , C, q CW and m exp eff for our sample are compared with different copper manganese, mixed oxide spinel 34,35,50 listed in Table 1.…”

“…(RCP) values correspond to about 48.21 and 44% of those observed in pure Gd at 5 T. It is worth noting that the (RCP) value is high. 34,65 Thus, our compound can be considered as active magnetic refrigerants. Fig.…”

“…31 Recently, there has been a swell of interest in materials containing copper and manganese oxides with spinel structures owing to their interesting magnetic properties. [33][34][35] 3d 3 ) occupy the octahedral site. [36][37][38] For the Cu 1.5 Mn 1.5 O 4 system, both the valance states of Cu ions (Cu 1+ /Cu 2+ ) and Mn ions (Mn 4+ ) and their site occupancies at the tetrahedral (A site) and octahedral (B site) sites have large exibilities and hence the affecting magnetic properties, it can be justied by superexchange coupling between the sublattices, and the fact that the local ferrimagnetic order of Mn 4+ ions on B sites can be disturbed by Cu 2+ on the same sites.…”