Sizable magnetic entropy change in bismuth-substituted La_0.75Bi_0.1Na_0.15MnO₃ manganite

Abstract

The sample La0.75Bi0.1Na0.15MnO3 exhibits large ΔSMaxm of 4.4 J kg−1 K−1 near room temperature (RT) at low field of 1.5 T (LF). The coexistence of long and short-range interactions leading to first order like phase transition is responsible for LFRT magnetic entropy change.

Magnetocaloric Effect in Lightly‐Doped Fe5Si3 Single Crystals

“…In the above discussion, the relative cooling power (RCP) was used to evaluate the cooling efficiency, which is inadequate especially for materials with low entropy change. [ 44 ] For low entropy change materials, the temperature averaged entropy change (TEC) is an appropriate parameter compared with that of RCP. Therefore, we further estimated the TEC of FMSP according to the equation $${\rm{TEC}}( {{T}_{lift}} ) = \frac{1}{{\Delta {T}_{lift}}}\ [ {\int_{{{T}_{mid} - \frac{{\Delta {T}_{lift}}}{2}}}^{{{T}_{mid} - \frac{{\Delta {T}_{lift}}}{2}}}{{\Delta S{{( T )}}_{\Delta H;T}dT}}} ]$$.…”

“…In the above discussion, the relative cooling power (RCP) was used to evaluate the cooling efficiency, which is inadequate especially for materials with low entropy change. [44] For low entropy change materials, the temperature averaged entropy change (TEC) is an appropriate parameter compared with that of RCP. Therefore, we further estimated the TEC of FMSP according to the equation TEC( [45] The estimated TEC for field changes of 0-0.5 to 0-1.5 T and ΔT lift of 2, 3, 6, and 9 K for both 𝜇 0 H⊥c and 𝜇 0 H//c are displayed in Figure 5.…”

Influence of heat sintering on the physical properties of bulk La0.67Ca0.33MnO3 perovskite manganite: role of oxygen in tuning the magnetocaloric response

“…A few examples for this class of materials with a giant MCE are Gd 5 Si 2 Ge 2 , 5,6 Fe-Rh alloys, 7,8 La(Fe,Si) 13 -based alloys, 9,10 MnAs Heusler alloys [11][12][13] and RE 1Àx A x Mn 1Ày TM y O 3 (RE -rare earth metal, A -divalent/monovalent ion, TM -transition metal) perovskite manganites. [14][15][16][17][18][19] Among perovskite manganites, lanthanum-based mixedvalence manganites with the general formula La 1Àx A x MnO 3 (A is mostly a divalent ion, Ca, Ba or Sr) show a variety of fascinating properties, like colossal magnetoresistance (CMR), [20][21][22] charge ordering (CO), 23,24 phase separation (PS), 25,26 the magnetocaloric effect (MCE), 1,[27][28][29][30] etc. For (La,Ca)MnO 3 , both end members LaMnO 3 and CaMnO 3 are typical antiferromagnets with T N close to 140 K and 130 K, respectively.…”

“…Among perovskite manganites, lanthanum-based mixed-valence manganites with the general formula La 1− x A x MnO 3 (A is mostly a divalent ion, Ca, Ba or Sr) show a variety of fascinating properties, like colossal magnetoresistance (CMR), 20–22 charge ordering (CO), 23,24 phase separation (PS), 25,26 the magnetocaloric effect (MCE), 1,27–30 etc. For (La,Ca)MnO 3 , both end members LaMnO 3 and CaMnO 3 are typical antiferromagnets with T N close to 140 K and 130 K, respectively.…”