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arXiv · 0805.3223

Origin of Metallic States at Heterointerface between Band Insulators LaAlO$_3$ and SrTiO$_3$

K. Yoshimatsu·R. Yasuhara·H. Kumigashira·M. Oshima
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Abstract

We have studied the electronic structure at the heterointerface between the band insulators LaAlO$_3$ and SrTiO$_3$ using $in situ$ photoemission spectroscopy. Our experimental results clearly reveal the formation of a notched structure on the SrTiO$_3$ side due to band bending at the metallic LaAlO$_3$/TiO$_2$-SrTiO$_3$ interface. The structure, however, is absent at the insulating LaAlO$_3$/SrO-SrTiO$_3$ interface. The present results indicate that the metallic states originate not from the charge transfer through the interface on a short-range scale but from the accumulation of carriers on a long-range scale.

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K. Yoshimatsu, R. Yasuhara, H. Kumigashira, M. Oshima. 2008-05-21. Origin of Metallic States at Heterointerface between Band Insulators LaAlO$_3$ and SrTiO$_3$. https://doi.org/10.1103/physrevlett.101.026802

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