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تسجيل مستخدم جديدSurface effects on the orbital order in the single layered manganite La0.5Sr1.5MnO4
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We report the first observation of `orbital truncation rods -- the scattering arising from the termination of bulk orbital order at the surface of a crystal. The x-ray measurements, performed on a cleaved, single-layered perovskite, La0.5Sr1.5MnO4, reveal that while the crystallographic surface is atomically smooth, the orbital `surface is much rougher, with an r.m.s. deviation from the average `surface of ~0.7nm. The temperature dependence of this scattering shows evidence of a surface-induced second order transition.
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