Related Experiment Video
Updated: Jun 3, 2026

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
A critical re-examination and a revised phase diagram of La(1 - x)Sr(x)CoO₃
1Department of Physics, Indian Institute of Science, Bangalore 560012, India. debphy@physics.iisc.ernet.in
Abstract:
We report the results of a comprehensive study on dc magnetization, ac susceptibility, and the magnetotransport properties of the La(1 - x)Sr(x)CoO₃(0 ≤ x ≤ 0.5) system. At higher Sr doping (x ≥ 0.18), the system exhibits Brillouin-like field cooled magnetization (M(FC)). However, for x < 0.18, the system exhibits a kink in the M(FC), a peak at the intermediate field in the thermoremnant magnetization and a non-saturating tendency in the M-H plot that all point towards the characteristic of spin glass behavior. More interestingly, dc magnetization studies for x < 0.18 do not suggest the existence of ferromagnetic correlation that can give rise to an irreversible line in the spin glass regime. The ac susceptibility study for x > 0.2 exhibits apparently no frequency dependent peak shift around the ferromagnetic transition region. However, a feeble signature of glassiness is verified by studying the frequency dependent shoulder position in χ('')(T) and the memory effect below the Curie temperature. But, for x < 0.18, the ac susceptibility study exhibits a considerable frequency dependent peak shift, time dependent memory effect, and the characteristic spin relaxation time scale τ(o) approximately 10(- 13) s. The reciprocal susceptibility versus temperature plot adheres to Curie-Weiss behavior and does not provide any signature of preformed ferromagnetic clusters well above the Curie temperature. The magnetotransport study reveals a cross over from metallic to semiconducting-like behavior for x ≤ 0.18. On the semiconducting side, the system exhibits a large value of magnetoresistance (upto 75%) towards low temperature and it is strongly connected to the spin dependent part of the random potential distribution in the spin glass phase. Based on the above observations, we have reconstructed a new magnetic phase diagram and characterized each phase with associated properties.
More Related Videos
Related Concept Videos
Phase Diagrams of Ternary Systems
Phase Diagrams
Imperfections in Crystal Structure: Non-Stoichiometric Defects
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Phase Diagram
Phase Diagram

