Direct observation of oxygen superstructures in manganites.
نویسندگان
چکیده
We report the observation of superstructures associated with the oxygen 2p states in two prototypical manganites using x-ray diffraction at the oxygen K edge. In the stripe order system Bi0.31Ca0.69MnO3, hole-doped O states are orbitally ordered, at the same propagation vector as the Mn orbital ordering, but no oxygen charge stripes are found at this periodicity. In La7/8Sr1/8MnO3, we observe a 2p charge ordering described by alternating hole-poor and hole-rich MnO planes that is consistent with some of the recent predictions.
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عنوان ژورنال:
- Physical review letters
دوره 99 20 شماره
صفحات -
تاریخ انتشار 2007