[14a-2H-1~11] 6.3 Oxide electronics

[14a-2H-7] Hard X-Ray Photoemission Study of LaAlO₃/(Nb:)SrTiO₃

〇Tomofumi Susaki^1,2, Shigenori Ueda³, Kosuke Matsuzaki^1,2, Toshihiro Kobayashi¹, Yoshitake Toda², Hideo Hosono^1,2 (1.MSL, Tokyo Tech, 2.MCES, Tokyo Tech, 3.NIMS)

Keywords:photoemission spectroscopy,band alignment,LaAlO3/SrTiO3

We have studied electronic states of LaAlO₃/SrTiO₃ and LaAlO₃/Nb:SrTiO₃ by hard x-ray photoemission spectroscopy and have found that (i) the core levels of SrTiO₃ are lowered in LaAlO₃/SrTiO₃ than in LaAlO₃/Nb:SrTiO₃, consistent with Kelvin probe measurements, and that (ii) the structure appears more clearly in the valence band spectrum of LaAlO₃/SrTiO₃ than in that of LaAlO₃/Nb:SrTiO₃.