相关论文: Size-Induced Exchange Bias Effect and Griffiths Ph…
The finite-size effect on the evolution of Griffiths phase (GP) is studied using nanoparticles of half-doped manganite Pr$_{0.5}$Sr$_{0.5}$MnO$_{3}$ with different average particle sizes but having similar structural parameters. All the…
The large, so-called colossal, magnetoresistivity of doped manganese oxides based on LaMnO3 has attracted considerable attention, but only one unusual feature of the ferromagnetic transition in these compounds. We examine in this paper the…
The exchange bias (EB) effect has been observed in magnetic Bi$_{0.9}$Gd$_{0.1}$Fe$_{0.9}$Ti$_{0.1}$O$_3$ nanoparticles. The influence of magnetic field cooling on the exchange bias effect has also been investigated. The magnitude of the…
Exchange bias (EB) phenomena have been observed in Nd2/3Ca1/3MnO3 colossal magnetoresistance perovskite below the Curie temperature $T_{C}$ = 70 K and attributed to an antiferromagnetic (AFM) - ferromagnetic (FM) spontaneous phase…
We have studied structural, magnetic and transport properties as a function of temperature and magnetic field in the electron doped manganite YxCa1-xMnO3, for 0<x<0.25. We found that in the paramagnetic regime, the magnetic susceptibility,…
Doping of the band insulator FeS$_2$ with Co on the Fe site introduces a small density of itinerant carriers and magnetic moments. The lattice constant, AC and DC magnetic susceptibility, magnetization, and specific heat have been measured…
We present a study of the magnetic properties of the electron doped manganites Ca1-xYxMnO3 (for 0<=x<=0.25) in the paramagnetic regime. For the less doped samples (x<=0.1) the magnetic susceptibility, c(T), follows a Curie-Weiss (CW) law…
The structural, magnetic, magnetocaloric and Griffiths phase (GP) disorder of non-stoichiometric perovskite manganites La_(0.8-x) Sr_(0.2-y) Mn_(1+x+y) O_3 are reported here. Determination of valence states and structural phases evidenced…
The effect of resistive switching in doped manganites being in the ferromagnetic state has been studied using resistive and magneto-optic methods. The visualization of magnetic structure of La0.75Sr0.25MnO3-x single crystals, and its…
The exchange bias (EB) in LaMn_{0.7}Fe_{0.3}O_3 is observed by the negative shift and training effect of the hysteresis loops, while the sample was cooled in external magnetic field. The analysis of cooling field dependence of EB gives the…
The dielectric behavior of half doped manganites La0.5Ca0.5-xSrxMnO3 (0.1 \leq \times \leq 0.4) with varying magnetic ground states has been studied. The real part of relative permittivity as a function of temperature {\epsilon}^'(T),…
We report on exchange bias effects in 10 nm particles of Pr0.5Ca0.5MnO3 which appear as a result of competing interactions between the ferromagnetic (FM)/anti-ferromagnetic (AFM) phases. The fascinating new observation is the demonstration…
Magnetic and magneto-functional behavior of a Fe-doped MnNiGe alloy with nominal composition Mn$_{0.85}$Fe$_{0.15}$NiGe have been investigated in ambient as well as in high pressure condition. The alloy undergoes first order martensitic…
Magnetization, magnetoresistance, and magnetodielectric measurements have been carried out on the half doped charge ordered manganite, Pr_0.5Ca_0.5MnO_3. The low temperature state is found to be strongly dependent on the oxygen…
In this report we show that in the perovskite manganite La_{1-x}Ca_{x}MnO_3 for a fixed x \approx 0.33, the magnetic transition changes over from first order to second order on reducing the particle size to nearly few tens of a nanometer.…
It is now widely accepted that the magnetic transition in doped manganites that show large magnetoresistance is a type of percolation effect. This paper demonstrates that the transition should be viewed in the context of the Griffiths phase…
The effect of doping of rare earth Gd 3+ ion replacing Nd 3+ in Nd0.7Sr0.3MnO3 is investigated in details. Measurements of resistivity, magnetoresistance, magnetization, linear and non linear ac magnetic susceptibility on chemically…
Polycrystalline La1-xPbxMnO3+-y (x = 0.3, 0.35, 0.4) solid solutions were prepared by solid state reaction method and their magnetic properties have been investigated. Rietveld refinement of X-ray powder diffraction patterns showed that all…
Exchange bias phenomenon is generally ascribed to the exchange coupling at the interfaces between ferromagnetic and antiferromagnetic layers. Here, we propose a bulk form of exchange bias in a single-phase magnet where the coupling between…
Pressure sensitivity (up to 1 GPa) of the electrical resistivity and of the ac susceptibility was measured for low electron doping levels of Ca$_{1-x}$Y$_x$MnO$_3$ (CYMO) and of Ca$_{1-x}$Sm$_x$MnO$_3$ (CSMO) ceramic samples (0.05 $\leq$ x…