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Time Dependent Effects and Transport Evidence for Phase Separation in La_{0.5}Ca_{0.5}MnO_{3}

M. Roy·J. F. Mitchell·P. Schiffer
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Abstract

The ground state of La_{1-x}Ca_{x}MnO_{3} changes from a ferromagnetic metallic to an antiferromagnetic charge-ordered state as a function of Ca concentration at x ~ 0.50. We present evidence from transport measurements on a sample with x = 0.50 that the two phases can coexist, in agreement with other observations of phase separation in these materials. We also observe that, by applying and then removing a magnetic field to the mainly charge-ordered state at some temperatures, we can "magnetically anneal" the charge order, resulting in a higher zero-field resistivity. We also observe logarithmic time dependence in both resistivity and magnetization after a field sweep at low temperatures.

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M. Roy, J. F. Mitchell, P. Schiffer. 2000-01-06. Time Dependent Effects and Transport Evidence for Phase Separation in La_{0.5}Ca_{0.5}MnO_{3}. https://doi.org/10.1063/1.372537

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