Nanoscale phase separation in manganites
نویسنده
چکیده
We study the possibility of nanoscale phase separation in manganites in the framework of the double exchange model. The homogeneous canted state of this model is proved to be unstable toward the formation of small ferromagnetic droplets inside an antiferromagnetic insulating matrix. For the ferromagnetic polaronic state we analyze the quantum effects related to the tails of electronic wave function and a possibility of electron hopping in the antiferromagnetic background. We find that these effects lead to the formation of the threshold for the polaronic state.
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1 Spin Superstructure Project (ERATO-SSS), Japan Science and Technology Agency (JST), AIST Central 4, Tsukuba 305-8562, Japan 2 Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8561, Japan, and CREST, JST, Kawaguchi, Saitama 332-0012, Japan ERATO multiferroics project, JST, c/o Department of Applied Physics , University of Tokyo, Tokyo 113-8656, Japan Department...
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