B.C. Zhao

Magnetic and transport properties in the Ti doped cobaltite Ca3Co4−xTixO9(0⩽x⩽0.8) single crystals

Single crystals of Ca3Co4−xTixO9 (x=0, 0.2, 0.4, 0.6, and 0.8) are grown by flux growth technique. The effect of Ti doping at Co site on magnetic and transport properties is studied. All samples show Curie-Weiss behavior at temperatures above 50K except for the x=0.8 sample, and the effective magnetic moment μeff increases with increasing Ti content. The free-doped sample Ca3Co4O9 shows a ferrimagnetic transition at 19K. However, a spin-glass transition at Tf(∼20K) appears for the Ti doped samples and the transition temperature Tf shifts to higher temperature as the Ti content increases. The magnetic moment values M at Tf and 5K under the applied field of 4.5T increase with increasing Ti doping content. The variation of the magnetic properties may be related to the induced extra Co2+ ions in the CoO2 layer by substituting Ti4+ for Co3+. The resistivity ρ of the x=0, 0.2, 0.4, and 0.6 samples shows metalliclike behavior at high temperatures and a broad metal-insulator (M-I) transition appears as the temper...

Structural, magnetic, and transport properties of the Cu-doped manganite La0.85Te0.15Mn1-xCuxO3 (0≤x≤0.20)

The effect of Cu-doping at Mn-site on structural, magnetic and transport properties in electron-doped manganites La0.85Te0.15Mn1-xCuxO3 has been investigated. Based on the analysis of structural parameter variations, the valence state of the Cu ion in Cu-doped manganites is suggested to be +2. All samples undergo the paramagnetic-ferromagnetic (PM-FM) phase transition. The Curie temperature decreases and the transition becomes broader with increasing Cu-doping level, in contrast, the magnetization magnitude of Cu-doping samples at low temperatures increase as x \leq 0.15. The insulator-metal (I-M) transition moves to lower temperatures with increasing Cu-doping content and disappears as x > 0.1. In addition, the higher temperature resistivity r peak in double-peak-like r(T) curves observed in no Cu-doping sample is completely suppressed as Cu-doping level x = 0.1 and r(T) curve only shows single I-M transition at the low temperature well below . The results are discussed according to the change of magnetic exchange interaction caused by Cu-doping.

Diamagnetism, transport, magnetothermoelectric power, and magnetothermal conductivity in electron-doped CaMn1−xVxO3 manganites

The effects of V doping on field-cooled magnetization MFC(T), zero-field-cooled magnetization MZFC(T), resistivity ρ, thermoelectric power S, and thermal conductivity κ in manganites CaMn1−xVxO3 (0.02⩽x⩽0.08) have been investigated systematically. As the V doping level exceeds 0.02, an anomalous “diamagnetism” has been observed. It is suggested that the force generated by the orbit rotation of eg electron in Mn3+O6 octahedron makes the spin tilt, as a result, the vector sum of individual spins may be along or opposite to the direction of the applied magnetic field, and macroscopically, the average magnetization exhibits positive or negative values. In addition, the transport mechanism in the high and low temperature ranges is dominated by the small polaron conduction and the variable-range-hopping conduction, respectively, according to the fitting analysis of the temperature dependence of Seebeck coefficient S(T) and resistivity ρ(T). Both S and κ peaks appearing at low temperature is gradually suppressed...

The effect of grain size on electrical transport and magnetic properties of La 0.9 Te 0.1 MnO 3.

Abstract The effect of grain size on structural, magnetic and transport properties in electron-doped manganites La0.9Te0.1MnO3 has been investigated. All samples show a rhombohedral structure with the space group R 3 ¯ C at room temperature. The Mn–O–Mn bond angle decreases and the Mn–O bond length increases with the increase of grain size. All samples undergo paramagnetic (PM)-ferromagnetic (FM) phase transitions and the interesting phenomenon that both magnetization and the Curie temperature TC decrease with increasing grain size is observed, which is suggested to mainly originate from the increase of the Mn–O bond length dMn–O. Additionally, ρ obviously increases with decreasing grain size due to the increase of both the height and width of tunneling barriers with decreasing grain size. The results indicate that both the intrinsic colossal magnetoresistance and the extrinsic interfacial magnetoresistance can be effectively tuned in La0.9Te0.1MnO3 by changing grain size.

Structural, magnetic, and transport properties in the Pr -doped manganites La 0.9 − x Pr x Te 0.1 MnO 3 ( 0 ⩽ x ⩽ 0.9 )

The effect of

The influence of Cr doping on the charge-ordering state in bilayered LaSr2Mn2O7

\mathrm{Pr}

Magnetic and electrical/thermal transport properties of Mn-doped Mn+1AXn phase compounds Cr2-xMnxGaC (0 《 x 《 1)

-doping on structural, magnetic and transport properties in electron-doped manganites

The magnetic, electrical transport and thermal transport properties of Fe-based antipervoskite compounds ZnCxFe3

{\mathrm{La}}_{0.9\ensuremath{-}x}{\mathrm{Pr}}_{x}{\mathrm{Te}}_{0.1}{\mathrm{MnO}}_{3}\phantom{\rule{0.3em}{0ex}}(0\ensuremath{\leqslant}x\ensuremath{\leqslant}0.9)

Large remnant polarization and magnetic field induced destruction of cycloidal spin structure in Bi1−xLaxFeO3 (0 ≤ x ≤ 0.2)

with fixed carrier concentration is investigated. The room temperature structural transition from rhombohedral

Magnetic and transport properties of La0.7Sr0.3Mn1?xTixO3 (0 ? x ? 0.5) films prepared by chemical solution deposition

(R\overline{3}C)