Magnetic phase transition and clustered state in Ca-doped lanthanum cobaltite and manganite with insulator ground states.

The transport and magnetic properties (ac linear and nonlinear (second and third orders) susceptibilities) are presented for La0.8Ca0.2MnO3 and La0.

Electric field driven destabilization of the insulating state in nominally pure LaMnO3.

We report an electric field driven destabilization of the insulating state in nominally pure LaMnO3 single crystal with a moderate field which leads to a resistive state transition below 300 K. The transition is between the insulating state in LaMnO3 and a high resistance bad metallic state that has a temperature independent resistivity. The transition occurs at a threshold field (Eth) that shows a steep enhancement on cooling.

The x-ray magnetic circular dichroism spin sum rule for 3d4 systems: Mn3+ ions in colossal magnetoresistance manganites.

The colossal magnetoresistance manganites La(0.87±0.02)Sr(0.

Optical and magneto-optical properties of ferromagnetic La(1-x)Ba(x)MnO3 single crystals.

The optical and magneto-optical properties of ferromagnetic La(1-x)Ba(x)MnO(3) single crystals with x=0.15, 0.20 and 0.

The evolution of Griffiths-phase-like features and colossal magnetoresistance in La(1-x)Ca(x)MnO(3) (0.18 ≤ x ≤ 0.27) across the compositional metal-insulator boundary.

Detailed measurements of the magnetic and transport properties of single crystals of La(1-x)Ca(x)MnO(3) (0.18 ≤ x ≤ 0.27) are summarized, and lead to the following conclusions.

Quantized spin waves in the metallic state of magnetoresistive manganites.

Spin wave measurements have been carried out in ferromagnetic (F) La(1-x)(Sr,Ca)(x)MnO(3) with x(Sr) = 0.15, 0.175, 0.

Is a Griffiths phase a prerequisite for colossal magnetoresistance?

Detailed measurements of the magnetic and transport behavior of the two La(1-x)Ca(x)MnO(3) single crystals exhibiting colossal magnetoresistance are summarized. The x=0.21 sample exhibits unusual exponents (delta = 20+/-1, gamma = 1.

Direct investigation of orbital ordering in a colossal magnetoresistance manganite by means of X-ray linear dichroism at the Mn L edge.

We have investigated for the first time the orbital ordering in a three-dimensional colossal magnetoresistance manganite, namely La(7/8)Sr(1/8)MnO3, by applying soft X-ray linear dichroism (XLD) to the Mn L edge. We found that the cooperative Jahn-Teller distorted orthorhombic phase, which is present at a temperature of 240 K, is probably accompanied by a predominantly cross type (x2 - z2)/(y2 - z2) orbital ordering. This result is discussed in the light of different exchange interaction models.

Electronic structure of A- and B-site doped lanthanum manganites: a combined X-ray spectroscopic study.

The electronic properties of a series of colossal magnetoresistance (CMR) compounds, namely LaMnO3, La(1-x)Ba(x)(MnO3 (0.2 < or = x < or = 0.55), La(0.

Twinning and structure of Eu(0.6)Sr(0.4)MnO3.

The crystal structure of europium strontium manganese trioxide, Eu(0.6)Sr(0.4)MnO3, has been refined using a multiply twinned single crystal containing six twin components.

Monoclinic La1-xBaxMnO3 (x=0.185) at 160 K.

Single-crystal X-ray diffraction has shown that lanthanum barium manganese trioxide, La0.815Ba0.185MnO3, is monoclinic (I2/c) below a first-order phase transition at 187.

Atomic scale spin-dependent STM on magnetite using antiferromagnetic STM tips.

STM tips made from antiferromagnetic MnNi have been used to investigate the atomic structure of the (001) and (111) surfaces of Fe3O4. The clean (001) surface displays a ( radical2 x radical2)R45 degrees superlattice, which is attributed to charge-ordering on the surface, where Fe(2+)-Fe2+ and Fe(3+)-Fe3+ dimers can be discriminated. The oxygen-terminated (111) surface is characterized by a hexagonal superlattice with a periodicity of 42 A.

Confined spin waves reveal an assembly of nanosize domains in ferromagneticLa1-xCaxMnO3 (x=0.17,0.2).

We report a study of spin waves in ferromagnetic La1-xCaxMnO3, at concentrations x=0.17 and x=0.2 very close to the metallic transition (x=0.

Giant volume magnetostriction and colossal magnetoresistance at room temperature in La(0.7)Ba(0.3)MnO(3).

Giant volume magnetostriction at room temperature is found for the first time in a La(0.7)Ba(0.3)MnO(3) single crystal, achieving 2.

Charge ordering and polaron formation in the magnetoresistive oxide La0.7Ca0.3MnO3.

Neutron scattering has been used to study the nature of the ferromagnetic transition in a single crystal of the perovskite La0. 7Ca0.3MnO3.