Resistivity and1/fnoise in nonmetallic phase-separated manganites
نویسندگان
چکیده
منابع مشابه
Spin-dependent Transport in Phase-separated Manganites
Starting from the assumption that ferromagnetically correlated regions exist in manganites even in the absence of long-range magnetic order, we construct a model of charge transfer due to the spin-dependent tunnelling of charge carriers between such regions. This model allows us to analyze the temperature and magnetic field dependence of resistivity, magnetoresistance, and magnetic susceptibili...
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Pr0.5Ca0.5Mn1−xCrxO3 (x= 0.015-0.05) undergoes an insulator-metal (I-M) transition below a temperature Tp driven by percolation of ferromagnetic metallic clusters in a charge ordered insulating matrix. Surprisingly, the I-M transition in these compounds is unstable against thermal cycling : Tp decreases and the resistivity at Tp increases upon temperature cycling between a starting temperature ...
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Low temperature resistivity of CMR manganites is investigated. At the ground state, conduction electrons are perfectly spin polarized, which is called half-metallic. From one-magnon scattering processes, it is discussed that the resistivity of a half metal as a function of temperature scales as ρ(T )− ρ(0) ∝ T . We take (Nd0.8Tb0.2)0.6Sr0.4MnO3 as an example to compare theory and experiments. T...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2001
ISSN: 0163-1829,1095-3795
DOI: 10.1103/physrevb.63.174424