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arXiv · 1112.0882

Polar Antiferromagnets Produced with Orbital-Order

Naoki Ogawa·Yasushi Ogimoto·Yoshiaki Ida·Yusuke Nomura·Ryotaro Arita·Kenjiro Miyano
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Abstract

Polar magnetic states are realized in pseudocubic manganite thin films fabricated on high-index substrates, in which a Jahn-Teller (JT) distortion remains an active variable. Several types of orbital-orders were found to develop large optical second harmonic generation, signaling broken-inversion-symmetry distinct from their bulk forms and films on (100) substrates. The observed symmetry-lifting and first-principles calculation both indicate that the modified JT q2 mode drives Mn-site off-centering upon orbital order, leading to the possible cooperation of "Mn-site polarization" and magnetism.

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Naoki Ogawa, Yasushi Ogimoto, Yoshiaki Ida, Yusuke Nomura, Ryotaro Arita, Kenjiro Miyano. 2011-12-05. Polar Antiferromagnets Produced with Orbital-Order. https://doi.org/10.1103/physrevlett.108.157603

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