Photoemission and x-ray absorption of the electronic structure of multiferroic RMnO 3 (R=Y,Er)

Abstract

Electronic structures of multiferroic RMnO 3 (R=Y,Er) have been investigated by employing photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS). We have found that Mn ions in RMnO 3 are in the trivalent high-spin state with the total spin of S=2. The occupied Mn (d xz-d yz) states lie deep below E F, while the occupied Mn (d xy-d x2-y2) states overlap very much with the O 2p states. It is observed that the PES spectral intensity of Mn 3d states is negligible above the occupied O 2p bands, suggesting that YMnO 3 is likely to be a charge-transfer insulator. The Mn d 3z2-r2 state is mostly unoccupied in the ferroelectric phase of YMnO 3. ©2005 The American Physical Society.