Magnetic properties of compacted ${\text{La}}_{0.8}{\text{Ca}}_{0.2}{\text{MnO}}_{3}$ manganite nanoparticles with average particle size 18 and 70 nm Curie temperatures ${T}_{\text{C}}\ensuremath{\approx}231\text{ }\text{K}$ ${T}_{\text{C}}\ensuremath{\approx}261\text{ }\text{K}$, respectively, have been investigated. The relative volume the ferromagnetic phase has estimated to be 52% for ensembles particles 92% particles. It was found that applied hydrostatic pressure enhances...

An exchange-bias (EB) effect observed in single crystal $\mathrm{ErFe}{\mathrm{O}}_{3}$ compensated ferrimagnet, exhibiting the EB field ${H}_{\mathrm{EB}}$ increasing and diverging upon approaching compensation temperature ${T}_{\mathrm{comp}}=45\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, changing sign with crossing ${T}_{\mathrm{comp}}$, is reported. The may be changed to opposite one by varying field-cooling protocol, depending on whether ${T}_{\mathrm{comp}}$ crossed decreasing or...

Measurements of electrical resistance, magnetization, ac magnetic susceptibility, and ferromagnetic resonance ${\mathrm{La}}_{0.82}{\mathrm{Ca}}_{0.18}{\mathrm{MnO}}_{3}$ single crystal were carried out at temperatures below above the Curie temperature, ${T}_{C}=180\ifmmode\pm\else\textpm\fi{}1\mathrm{K}.$ A state mixed phases, metallic insulating, is clearly evident from measurements electron resonance, ${T}_{C}.$ The effect applied hydrostatic pressure P field H on resistive properties...

Magnetic properties of electron-doped ${\text{La}}_{0.2}{\text{Ca}}_{0.8}{\text{MnO}}_{3}$ manganite nanoparticles with average particle size ranging from 15 to 37 nm, prepared by the glycine-nitrate method, have been investigated in temperature range 5--300 K and magnetic fields up 90 kOe. A monotonous enhancement weak ferromagnetism linked reduction was observed for all nanoparticles. hysteresis loops also indicate size-dependent exchange bias effect displayed horizontal vertical shifts...

Magnetic properties of compacted $50\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ ${\mathrm{CaMnO}}_{3\ensuremath{-}\ensuremath{\delta}}$ (CMO) nanoparticles have been investigated. Measurements ac-susceptibility exhibit upon cooling two magnetic transitions at $T\ensuremath{\sim}270\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ accompanied by a small spontaneous moment and para-antiferromagnetic (AFM) transition ${T}_{\text{N}}\ensuremath{\sim}120\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, observed...

The unconventional exchange-bias (EB) effect in single crystals of $R\mathrm{Fe}{\mathrm{O}}_{3}(R=\mathrm{Nd},\phantom{\rule{0.28em}{0ex}}\mathrm{Sm})$ compensated ferrimagnets (fMs), composed two antiferromagnetically (AFM) coupled $R$ and Fe sublattices with opposite ferromagnetic (FM) moments, exhibiting the FM moment reversal via a fast spin switching is reported. In ${\mathrm{NdFeO}}_{3}$, EB anisotropy field emerges diverges upon approaching compensation temperature...

The origin of magnetism in atomically disordered transition-metal--nonmagnetic (i.e., FeAl) alloys has been investigated by dichroism and diffraction measurements at high pressure band structure calculations. results show that, contrast to earlier studies, besides the effects local environment magnetic ions, disorder-induced lattice changes play a key role properties these systems. We demonstrate experimentally theoretically that about 35--45% moment ${\mathrm{Fe}}_{60}{\mathrm{Al}}_{40}$...

The exchange-bias (EB) effect with sign reversal was found in $\mathrm{LuF}{\mathrm{e}}_{0.5}\mathrm{C}{\mathrm{r}}_{0.5}{\mathrm{O}}_{3}$ ferrite-chromite, which is a weak ferrimagnet below ${T}_{\mathrm{N}}=265\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, exhibiting antiparallel orientation of the ferromagnetic (FM) moments Fe and Cr sublattices due to opposite Fe-Cr Dzyaloshinskii vector, as compared that Fe-Fe Cr-Cr. FM studied compound compensate each other at temperature...

Exchange bias (EB) related to magnetization reversal fields was found in a single-crystal of Ni4Nb2O9, compensated ferrimagnet consisting two Ni2+ ferromagnetic sublattices with opposite moments, associated differently distorted honeycomb-like layers the ab plane, alternating along c axis. The EB field is significant near compensation temperature Tcomp=33K, it increases rapidly as approaches Tcomp, and changes sign when crossing showing large gap 3.5 kOe. also diverges at Tcomp reaches 10...

Ferromagnetic and transport properties of ${\mathrm{La}}_{0.8}{\mathrm{Ca}}_{0.2}{\mathrm{MnO}}_{3}$ ${\mathrm{La}}_{0.78}{\mathrm{Ca}}_{0.22}{\mathrm{MnO}}_{3}$ single crystals were studied in temperature range $4.2\mathrm{K}<T<300\mathrm{K}$ under hydrostatic pressure up to 12 kbar. It was found that the above compounds exhibit different shifts Curie temperatures ${T}_{C}$ pressure. For ${\mathrm{dT}}_{C}/dP\ensuremath{\approx}0.3\mathrm{K}/\mathrm{k}\mathrm{b}\mathrm{a}\mathrm{r},$...

Pressure effect on magnetic order and anisotropy of low-doped ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}\mathrm{Co}{\mathrm{O}}_{3}$ $(0.1\ensuremath{\leqslant}x\ensuremath{\leqslant}0.2)$ ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Co}{\mathrm{O}}_{3}$ $(0.1\ensuremath{\leqslant}x\ensuremath{\leqslant}0.3)$ single crystals ceramics was studied by magnetization measurements. It found that applied hydrostatic pressure leads to a quite different ferromagnetic (FM)...

The magnetic properties of nanocrystalline manganites La1−xMnO3+δ with particle size 20 (LMO20), 25 (LMO25), and 30 nm (LMO30), prepared by the citrate method, have been investigated in temperature range 5–320 K, field up to 90 kOe under quasi-hydrostatic pressures 14.5 kbar. studies involve sequential zero-field-cooled magnetization (M) measurements followed during cooling same (H) complementary ac susceptibility. Additional M versus H were carried out at ambient applied pressures. All...

Magnetic properties of nanocrystalline ${\text{LaCoO}}_{3}$ with particle size 25, 30, 32, and 38 nm, prepared by the citrate method, were investigated in temperature range 2--320 K, magnetic field up to 50 kOe, under hydrostatic pressure 11 kbar. All nanoparticles exhibit weak ferromagnetism below ${T}_{C}\ensuremath{\approx}85\text{ }\text{K}$, agreement recent observation on particles tensile thin films. It was found that decreasing size, i.e., increasing surface volume ratio, unit-cell...

An unusual exchange bias (EB) effect in single-crystalline $\mathrm{GdCr}{\mathrm{O}}_{3}$ compensated ferrimagnet (fM), composed of two antiferromagnetically coupled Gd and Cr sublattices, presenting opposite ferromagnetic (FM) moments, is reported. It shown that the temperature- or field-induced fast reversal net FM moment may be identified as a switching between spin configurations, attendant with abrupt drop Zeeman energy...

The compensated ferrimagnet orthoferrite $\mathrm{ErFe}{\mathrm{O}}_{3}$ exhibits the exchange bias (EB) effect, which was previously detected as traditional shift of magnetization hysteresis loops $M$ vs $H$ near compensation temperature ${T}_{\mathrm{comp}}=45\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. This paper shows that another specific phenomenon, temperature-driven spin switching and bias, occurs in this ferrimagnet. Namely, EB manifests itself $T$, upon successive cooling heating a...

Effects of hydrostatic pressure up to $11\phantom{\rule{0.3em}{0ex}}\mathrm{kbar}$ on the magnetic and transport properties ${\mathrm{Pr}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Mn}{\mathrm{O}}_{3}$ (PSMO) were investigated in single crystals with various doping level: $x=0.22,0.24,0.26$, a wide range temperature. In similarity other low doped manganites, PSMO exhibits metal insulator transition magnetoresistance maxima at same temperature $T={T}_{\mathit{MI}}$. It was found that...

Transport and magnetic properties of compacted LaMnO3+δ manganite nanoparticles an average size 18 nm have been investigated in the temperature range 5–300 K. The exhibit a paramagnetic-to-ferromagnetic (FM) transition at Curie TC ∼ 246 However, spontaneous magnetization disappears higher about 270 It was found that low temperatures FM core occupies 50% particle volume. dependence resistivity shows metal–insulator low-temperature upturn below minimum T 50 transport is controlled by charging...

Pressure effect on magnetic properties of polycrystalline La${}_{1\ensuremath{-}x}$Ba${}_{x}$CoO${}_{3}$ (0.1 \ensuremath{\leqslant} $x$ 0.5) was studied by magnetization measurements in the temperature range 5--240 K, field up to 16 kOe, and under hydrostatic pressure 10.5 kbar. For low-doped cobaltites ($x$$=$0.1,0.15), it found that applied enhances ferromagnetic (FM) cluster phase, resulting an increase both spontaneous FM moment transition clusters ${T}_{C}^{\mathrm{cl}}$, while...

We report the structural and magnetic properties of La0.2Ca0.8MnO3 nanoparticles synthesized by a chemical route, having an average diameter 15 nm. Synchrotron experiments performed in temperature range 80−300 K have shown that below 200 transition from room orthorhombic Pnma to monoclinic P21/m space group, associated with orbital ordering, survives studied particles, although this is highly suppressed comparison bulk. The magnetization these particles exhibits appearance ferromagnetic...

Recent experiments showed magnetic moment reversal and pronounced exchange-bias (EB) effect in the vicinity of compensation temperature ${T}_{\mathrm{comp}}$ orthoferrites $R\mathrm{Fe}{\mathrm{O}}_{3}$ ($R=\mathrm{Nd}$, Sm, Er). Although different exhibit diverse $R$-Fe interactions, values, spin-reorientation temperatures, EB field like manner emerges diverges upon approaching changes its sign with crossing ${T}_{\mathrm{comp}}$. In order to explain these observations, a mean-field theory...

Spontaneous and field-dependent spin switching (magnetization reversal) has been studied in the compensated ferrimagnet ${\mathrm{NdFeO}}_{3}$. The temperature ${T}_{\mathrm{sw}}$ monotonically approaches compensation ${T}_{\mathrm{comp}}$ with an increase applied magnetic field above ${T}_{\mathrm{comp}}\ensuremath{\approx}9\phantom{\rule{0.28em}{0ex}}\mathrm{K}$. However, below ${T}_{\mathrm{comp}}$, a sharp drop towards low temperatures simultaneous magnetization jump...