Momentum dependence of orbital excitations in Mott-insulating titanates.
نویسندگان
چکیده
High-resolution resonant inelastic x-ray scattering has been used to determine the momentum dependence of orbital excitations in Mott-insulating LaTiO(3) and YTiO(3) over a wide range of the Brillouin zone. The data are compared to calculations in the framework of lattice-driven and superexchange-driven orbital ordering models. A superexchange model in which the experimentally observed modes are attributed to two-orbiton excitations yields the best description of the data.
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ورودعنوان ژورنال:
- Physical review letters
دوره 103 10 شماره
صفحات -
تاریخ انتشار 2009