The low field susceptibility versus temperature has been studied for the series of colossal magnetoresistive (CMR) manganites Ln0.7Ca0.3-xSrxMnO3 (Ln = Pr, x = 0.10, 0.05, 0; Ln = Nd, x = 0). The effect of the average size of the interpolated cation upon Tc is confirmed for the larger sizes (Ln = Pr, x = 0.10, 0.05) showing a classical ferromagnetic behavior at low temperature in agreement with the neutron diffraction studies. For a smaller size of the A-site cation (Ln = Pr or Nd, x = 0) an original behavior is observed: the χ′(T) curves show a spin-glass-like behavior with a cusp at Tcusp, whereas the neutron diffraction data in zero magnetic field evidence a ferromagnetic component starting around Tcusp.

Upadhyayula V Varadaraju

Department Of Chemistry

Composition effects

Ferromagnetism

Magnetic fields

Magnetic permeability

Magnetoresistance

Neutron diffraction

Thermal effects

COLOSSAL MAGNETORESISTANCE (CMR) MANGANITES

Spin glasses

Manganese compounds

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

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IIT Madras

AC susceptibilities and size effect in Ln0.7(Sr, Ca)0.3MnO3 CMR manganites

Journal of Magnetism and Magnetic Materials

Magnetization relaxation and AC-susceptibility measurements have been carried out on a disordered (La,Y)1-xCaxMnO3 (x = 0.25, 0.3 and 0.5) system where 〈r(La,Y)〉 = 〈rPr〉 = 1.18 Å. Resistivity and low-field susceptibility measurements suggest that the sample with x = 0.25 develops a dominant ferromagnetic component below 130 K. With increase of x, the ferromagnetic component decreases at the benefit of a charge-ordered antiferromagnetic one. At low temperatures, for x = 0.3, the magnetic frustration due to those two kinds of competing interactions leads to spin-glass-like behavior. This behavior is more pronounced for x = 0.5 as the strength of these competing interactions becomes equal. Magnetization relaxation measurements show that aging phenomenon exists in all the samples. The parameters obtained by fitting the M(t) data with a fractional exponential function are correlated with the transport and other magnetic properties. © 1998 Elsevier Science B.V. All rights reserved.

Magnetization relaxation and aging in spin-glass (La,Y)1-xCaxMnO3 (x = 0.25, 0.3 and 0.5) perovskite

Physical Review B

Evidence for 2D-3D magnetic ordering of Gd in high-Tc-relatedCaGdCuO3Cl andCa4R2Cu3O8Cl4(R=Gd,Sm)

Physical Review Letters

Spin-Glass Insulator State in (Tb-La)2/3Ca1/3MnO3Perovskite

Neutron diffraction evidence for an antiferromagnetic ordering in the CMR manganites Pr0.7Ca0.3−xSrxMnO3

Solid State Communications

Giant magnetoresistance ratios superior to 1011 in manganese perovskites

Science

A First-Order Phase Transition Induced by a Magnetic Field

Journal	Data powered by TypesetJournal of Magnetism and Magnetic Materials
Publisher	Data powered by TypesetElsevier
ISSN	03048853
Open Access	No