Dinh Chi Linh

Coexistence of short- and long-range ferromagnetic order in La0.7Sr0.3Mn1−xCoxO3 compounds

Polycrystalline La0.7Sr0.3Mn1−xCoxO3 (x = 0.0–1.0) samples were synthesized by solid-state reaction. Structural and magnetization studies reveal the replacement of Co for Mn in La0.7Sr0.3Mn1−xCoxO3, and the decrease of the Curie temperature (TC) from 360 K (for x = 0) to 224 K (for x = 1). Positive slopes observed in the H/M versus M2 curves prove all the samples undergo a second-order magnetic phase transition. By analysis of the M(H) data at temperatures around TC using the Kouvel-Fisher method, we obtained the values of critical parameters (TC, β, γ, and δ). The results suggest an existence of short-range FM order in the sample x = 0 with β = 0.377. Meanwhile, for the case of Co-doped samples, their β values in the range of 0.403–0.457 indicate a coexistence of short and long-range FM order. This means that Co-doping favors establishing FM long-range order in La0.7Sr0.3Mn1−xCoxO3. From M(H) data, we have also determined the magnetic entropy change (ΔSm) for the samples. We have found that the ΔSm(T) cu...

Magnetic and Magnetocaloric Properties of La 0.8– x Ag x Ca 0.2 MnO 3 Exhibiting the Crossover of First- and Second-Order Phase Transitions

This paper presents the magnetocaloric properties of polycrystalline La0.8– x Ag x Ca0.2MnO3 manganites (

Influence of Crystallite Size on Magnetocaloric Effect and Critical Behavior La 0.7 Sr 0.3 Mn 0.92 Co 0.08 O 3 Nanoparticles

x = 0.0

Magnetic and magnetocaloric properties in Ba-doped La0.7Ca0.3MnO3 nanoparticles

, 0.05, and 0.1) prepared by solid-state reaction. The results reveal that an Ag-concentration increase leads to a slight increase of the Curie temperature (

Magnetocaloric Effect in La0.7Ca0.25Ba0.05MnO3 Nanocrystals Exhibiting the Crossover of First- and Second-Order Magnetic Phase Transformation

T_{C})

Magnetic and magnetocaloric properties in second-order phase transition La1−xKxMnO3 and their composites

, and broadens the ferromagnetic–paramagnetic phase-transition region. The temperature dependences of the magnetic entropy change,

Critical properties around the ferromagnetic-paramagnetic phase transition in La0.7Ca0.3-xAxMnO3 compounds (A = Sr, Ba and x = 0, 0.15, 0.3)

\Delta S_{m}(T)

Na-doped La0.7Ca0.3MnO3 compounds exhibiting a large magnetocaloric effect near room temperature

, for the samples have also been calculated using Maxwell’s relation. As a function of temperature,

Electrical and magnetic properties of La0.7Ca0.3Mn0.9Co0.1O3 locating at a threshold of the first- and second-order phase transitions

-\Delta S_{m}(T)

Original ArticleLong-range ferromagnetism and magnetocaloric effects in rapidly quenched Ni50−xCoxMn50−yAly ribbons

curve shows the maximum value (denoted as