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Unveiling New Magnetic Phases of Undoped and Doped Manganites

Takashi Hotta·Mohammad Moraghebi·Adrian Feiguin·Adriana Moreo·Seiji Yunoki·Elbio Dagotto
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Abstract

Novel ground-state spin structures in undoped and lightly-doped manganites are here investigated based on the orbital-degenerate double-exchange model, by using mean-field and numerical techniques. In undoped manganites, a new antiferromagnetic (AFM) state, called the E-type phase, is found adjacent in parameter space to the A-type AFM phase. Its structure is in agreement with recent experimental results. This insulating E-AFM state is also competing with a ferromagnetic metallic phase as well, suggesting that large magneto-resistant effects could exist even in undoped Mn oxides. For doped layered manganites, the phase diagram includes another new AFM phase of the ${\rm C_x E_{1-x}}$-type. Experimental signatures of the new phases are discussed.

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Takashi Hotta, Mohammad Moraghebi, Adrian Feiguin, Adriana Moreo, Seiji Yunoki, Elbio Dagotto. 2003-01-04. Unveiling New Magnetic Phases of Undoped and Doped Manganites. https://doi.org/10.1103/physrevlett.90.247203

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