The manganese oxides of general formula RE1−xMxMnO3 (RE = rare earth, M = Ca, Sr, Ba, Pb) have remarkable interrelated structural, magnetic and transport properties induced by the mixed valence (3+–4+) of the Mn ions. In particular, they exhibit very large negative magnetoresistance, called colossal magnetoresistance (CMR), in the vicinity of metal–insulator transition for certain compositions. In this review paper, we summarize the most important features of the physics of the CMR manganites. The growth techniques for manganese oxide thin films, which are the basic material for potential applications, are reviewed and their structure and morphology examined in relation to growth parameters. The effects of epitaxial strains on the physical properties are discussed. Early works on superlattices and devices are presented.

http://iopscience.iop.org/article/10.1088/0022-3727/36/8/201/pdf

CMR manganites: physics, thin films and devices

Colossal-magnetoresistance materials: manganites and conventional ferromagnetic semiconductors

Giant magnetoresistance (GMR) is found for manganate perovskites of the formula Ln{sub 1-x}A{sub x}MnO{sub 3} (Ln = rare earth, A = dipositive ion). Changes in GMR near the critical temperature and the insulator-metal transition temperature were quantified as was the relationship between the radius of A and GMR. The electron transport properties of these manganates are discussed.

Giant magnetoresistance and related properties of rare-earth manganates and other oxide systems

Electron spin resonance measurements in La1−xSrxMnO3

https://www.tandfonline.com/doi/pdf/10.1088/1468-6996/16/2/026001

Electronic conduction in La-based perovskite-type oxides

A semiconductor-metal transition occurring just below the Curie temperature TC was observed in single crystals of perovskite La1-xSrxMnO3 for x>or=0.175. For x or=0.13 whereas huge MR persists well below TC for the x=0.10 sample, which is probably due to a non-collinear spin configuration.

https://iopscience.iop.org/article/10.1088/0953-8984/7/35/008/pdf

Transport properties and magnetic behaviour of La1-xSrxMnO3 single crystals

The orthorhombic twinned microstructure of stoichiometric LaMnO3 has been investigated and interpreted within the framework of the ferroelastic theory. One must infer the existence of a very-high-temperature cubic phase, unobserved until now. The orthorhombic and rhombohedral microstructures of La1—x Sr x MnO3 solid solutions (0 < x < 0.35) may then be easily interpreted, and the characteristics of their twinning systems predicted.

A. M. de Leon Guevara

Papers

Transport properties and magnetic behaviour of La1-xSrxMnO3 single crystals

Twinned microstructure of La1-xSrxMnO3 solid solutions

Conductivity and magnetoresistance of La1−xSrxMnO3 and La1−xSrxMn1−yMgyO3 single crystals