A phenomenological model for the pressure sensitivity of the Curie temperature in hole-doped manganites

Abstract

We performed high pressure experiments on La(0.8)Ca(0.2-x)Sr(x)MnO(3) (LCSMO) (0<x< 0.2) ceramic samples in order to analyze the validity of the well known relation between the A mean ionic radius (<rA>) and the Curie temperature Tc of hole-doped manganites at a fixed doping level and for doping values below the 0.3 (Mn+4/Mn+3) ratio. By considering our results and collecting others from the literature, we were able to propose a phenomenological law that considers the systematic dependence of Tc with structural and electronic parameters. This law predicts fairly well the pressure sensitivity of Tc, its dependence with the A-cation radius disorder and its evolution in the high pressure range. Considering a Double Exchange model, modified by polaronic effects, the phenomenological law obtained for Tc can be associated with the product of two terms: the polaronic modified bandwidth and an effective hole doping.

5 pages, 7 figures, corresponding author: C. Acha ([email protected])

References in corpus (9)

• Colossal Magnetoresistant Materials: The Key Role of Phase Separation
• Pressure-tuning of the electron-phonon coupling: the insulator to metal transition in manganites
• Pressure effects on charge, spin, and metal-insulator transitions in narrow bandwidth manganite Pr${}_{1-x}$Ca${}_x$MnO${}_3$
• Effect of substrate-induced strain on transport and magnetic properties of epitaxial La_0.66Sr_0.33MnO_3 thin films
• Suppression of Ferromagnetic Double Exchange by Vibronic Phase Segregation
• Effects of Pressure on Electron Transport and Local Structure of Manganites: Low to High Pressure Regime
• Evidences of a consolute critical point in the Phase Separation regime of La(5/8-y)Pr(y)Ca(3/8)MnO(3) (y = 0.4) single crystals
• Revealing polarons with high pressure on low electron-doped manganites
• High-Pressure Phase Diagram in the Manganites: a Two-site Model Study