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Electronic Structure of Charge- and Spin-controlled Sr_{1-(x+y)}La_{x+y}Ti_{1-x}Cr_{x}O_{3}

H. Iwasawa·K. Yamakawa·T. Saitoh·J. Inaba·T. Katsufuji·M. Higashiguchi·K. Shimada·H. Namatame·M. Taniguchi
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Abstract

We present the electronic structure of Sr_{1-(x+y)}La_{x+y}Ti_{1-x}Cr_{x}O_{3} investigated by high-resolution photoemission spectroscopy. In the vicinity of Fermi level, it was found that the electronic structure were composed of a Cr 3d local state with the t_{2g}^{3} configuration and a Ti 3d itinerant state. The energy levels of these Cr and Ti 3d states are well interpreted by the difference of the charge-transfer energy of both ions. The spectral weight of the Cr 3d state is completely proportional to the spin concentration x irrespective of the carrier concentration y, indicating that the spin density can be controlled by x as desired. In contrast, the spectral weight of the Ti 3d state is not proportional to y, depending on the amount of Cr doping.

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H. Iwasawa, K. Yamakawa, T. Saitoh, J. Inaba, T. Katsufuji, M. Higashiguchi, K. Shimada, H. Namatame, M. Taniguchi. 2006-01-11. Electronic Structure of Charge- and Spin-controlled Sr_{1-(x+y)}La_{x+y}Ti_{1-x}Cr_{x}O_{3}. https://doi.org/10.1103/physrevlett.96.067203

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