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In-plane anisotropy of the electronic structure for the charge/orbital-ordered state in half-doped manganite with layered structure

Y. S. Lee·S. Onoda·T. Arima·Y. Tokunaga·J. P. He·Y. Kaneko·N. Nagaosa·Y. Tokura
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Abstract

We report on the in-plane anisotropy of the electronic response in the spin/charge/orbital ordered phase of a half-doped layered-structure manganite. The optical conductivity spectra for a single domain of Eu$_{1/2}$% Ca$_{3/2}$MnO$_{4}$ unambiguously show the anisotropic charge dynamics which well corresponds to the theoretical calculation: the optical conductivity with the polarization along the zigzag ferromagnetic chain direction exhibits a smaller gap and a larger intensity at lower energies than that of the perpendicular polarization mostly due to the charge/orbital ordering and the associated quantum interference effect.

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Y. S. Lee, S. Onoda, T. Arima, Y. Tokunaga, J. P. He, Y. Kaneko, N. Nagaosa, Y. Tokura. 2006-06-05. In-plane anisotropy of the electronic structure for the charge/orbital-ordered state in half-doped manganite with layered structure. https://doi.org/10.1103/physrevlett.97.077203

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