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Two-phase behavior in strained thin films of hole-doped manganites

Amlan Biswas·M. Rajeswari·R. C. Srivastava·Y. H. Li·T. Venkatesan·R. L. Greene·A. J. Millis
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Abstract

We present a study of the effect of biaxial strain on the electrical and magnetic properties of thin films of manganites. We observe that manganite films grown under biaxial compressive strain exhibit island growth morphology which leads to a non-uniform distribution of the strain. Transport and magnetic properties of these films suggest the coexistence of two different phases, a metallic ferromagnet and an insulating antiferromagnet. We suggest that the high strain regions are insulating while the low strain regions are metallic. In such non-uniformly strained samples, we observe a large magnetoresistance and a field-induced insulator to metal transition.

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Amlan Biswas, M. Rajeswari, R. C. Srivastava, Y. H. Li, T. Venkatesan, R. L. Greene, A. J. Millis. 1999-10-29. Two-phase behavior in strained thin films of hole-doped manganites. https://doi.org/10.1103/physrevb.61.9665

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