Complex orbital state in manganites
نویسندگان
چکیده
The eg-orbital states with complex coefficients of the linear combination of x2 − y2 and 3z2 − r2 are studied for the ferromagnetic state in doped manganites. Especially the focus is put on the competition among uniform complex, staggered complex, and real orbital states. As the hole-doping x increases, the real, the canted complex, and the staggered complex orbital states appears successively. Uniform complex state analoguous to Nagaoka ferromagnet does not appear. These complex states can be expressed as a resonating state among the planer orbitals as the orbital liquid, accompanied by no Jahn-Teller distortion. 71.27.+a, 75.30.-m, 75.30.Et Typeset using REVTEX
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