Journal ArticleDOI
Colossal magnetoresistance of ferromagnetic manganites: Structural tuning and mechanisms.
Josep Fontcuberta,Benjamín Martínez,A. Seffar,S. Piñol,José Luis García-Muñoz,Xavier Obradors +5 more
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TLDR
The amplitude $\ensuremath{\rho}(T,H)$ and temperature ${T}_{M}$ and CMR are found to be controlled by the radius of the lanthanide $({L}^{3+})$ which modifies the bending of the Mn-O-Mn bond.Abstract:
The amplitude $\ensuremath{\Delta}\ensuremath{\rho}(T,H)/\ensuremath{\rho}$ and temperature ${T}_{M}$, where the colossal magnetoresistance (CMR) response of ${L}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ manganites are maximum, are found to be controlled by the radius of the lanthanide $({L}^{3+})$ which modifies the bending of the Mn-O-Mn bond. Increasing the bond distortion lowers ${T}_{M}$ and enhances $\ensuremath{\Delta}\ensuremath{\rho}(T,H)/\ensuremath{\rho}$. Enhanced CMR arises from (1) a shift to lower temperatures of ${T}_{M}$, (2) a reduced mobility of the doping holes, and (3) an increase of the coupling between itinerant and localized electrons. The resistivity $\ensuremath{\rho}\left(H\right)$ follows an $\ensuremath{\approx}{\mathrm{BM}}^{2}\left(H\right)$ law and the parameter $B$ is also tuned by the Mn-O-Mn bond angle. The narrowing of the electronic bandwidth is the fundamental parameter controlling the observed CMR.read more
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Electrical transport properties of La0.845Sr0.155MnO3:Kx (0 ≤ x ≤ 0.2) composites
TL;DR: In this article, the electrical conduction mechanisms on the metallic region have been investigated and the electrical resistivity of the insulating region was explained via the variable-range hopping model.
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Conduction and disorder in -based materials
N. G. Bebenin,V. V. Ustinov +1 more
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The effect of holmium doping on the magnetic and transport properties of
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A-site-disorder-dependent magnetocaloric properties in the mono-valent-metal doped La0.7Ca0.3MnO3 manganites
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