Magnetocaloric effect, specific heat and adiabatic temperature change of HoxEr1−xN (x=0.25, 0.5, 0.75)

Spin reorientation and the magnetocaloric effect in HoyEr(1−y)N

“…It is worth noticing that M B vs. B curves for h111i and h110i are close compared with h001i ones, leading the same anisotropic behavior observed in DS T vs. T curves. The open circles represent the experimental data, 12 which are well reproduced by our calculations considering the field applied along h001i direction. The calculated results predict an increase of about 70% in DS T at critical temperature if the sample ErN was produced as monocrystal and the magnetic field change applied along the h111i direction.…”

“…For example, existence and stability of several magnetic arrangements (cone-, screw-, fan-, and ferromagnetic-types structures) were studied in MnP single crystal; 3 the discovery of an anomaly in the paramagnetic compound PrNi 5 , in which the magnetic entropy increases increasing magnetic field; 4 the influence of the charge-ordering 5 on heat capacity and DS T in manganite Nd 0.5 Sr 0.5 MnO 3 ; giant MCE caused by rotation of the magnetization vector in NdCo 5 single crystal; 6 evidences for Bose-Einstein condensate ground state in the spin dimer system Sr 3 Cr 2 O 8 have been addressed in the literature through heat capacity and MCE measurements. 7 Experimental investigations on the magnetocaloric effect have been performed in rare earth mononitrides systems [8][9][10][11][12] RN (R ¼ Er, Ho, Dy, Tb, and Gd) and in binary rare earth systems Gd y Tb 1Ày N, Tb y Ho 1Ày N, Gd y Dy 1Ày N, and Ho y Er 1Ày N. Some advantages were pointed out in the above references to consider rare earth mononitrides as refrigerant materials to be used in magnetic refrigeration, especially for the liquefaction of hydrogen. The raised main advantages are (1) refrigerants based in rare earth mononitrides are inert to hydrogen, i.e., do not change properties even in contact with hydrogen; and (2) Rare earth mononitrides are formed in NaCl crystalline structure presenting high rare earth packing density, also the cubic lattice parameter changes linearly (obeying the Vegard's law) with rare earth ions concentration.…”

“…For example, heat capacity and magnetic measurements for temperature dependence of DS T in HoN showed a large discrepancy not yet explained. 12 The theoretical description of the magnetic properties and magnetocaloric effect in rare earth doped compounds such as Ho y Er 1Ày N is somewhat complicated due to the existence of two types of rare earth ions. This type of disordered problem can be addressed by Classical Monte Carlo Simulations 13 or by an extended mean field approach.…”

Magnetocaloric Effect of Rare Earth Nitrides

“…1). This is compared with kJ/K m [15] obtained for HoN with to 0 T (Note the data in Fig. 2 are for to 0 T.).…”

“…The area below the curve, , corresponds to the heat capacity, and this is the key property for a regenerator material used in a cryogenic cooling system. As we have previously reported, the heat capacity of Ho-ErN [15] is larger than those of Er3Ni or Gd Er Rh, which are now used as regenerator materials [16], [17]. Fig.…”