Temperature memory and resistive glassy behaviors of a perovskite manganite

Physical Review B (Impact Factor: 3.66). 02/2008; 77(21):214406. DOI: 10.1103/PhysRevB.77.214406
Source: arXiv

ABSTRACT This paper reports the observations of long-time relaxation, aging, and temperature memory behaviors of resistance and magnetization in the ferromagnetic state of a polycrystalline La0.7Ca0.3Mn0.925Ti0.075O3 compound. The observed glassy dynamics of the electrical transport appears to be magnetically originated and has a very close association with the magnetic glassiness of the sample. Phase separation and strong correlation between magnetic interactions and electronic conduction play the essential roles in producing such a resistive glassiness. We explain the observed effects in terms of a coexistence of two competing thermomagnetic processes, domain growth and magnetic freezing, and propose that hole-doped perovskite manganites can be considered as "resistive glasses". Comment: Submitted to PRB

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