Abstract
The origin of electronic states at the basis of the 2DEG found in conducting LaAlO 3 /SrTiO 3 interfaces (5 u.c. LaAlO 3 ) is investigated by resonant photoemission experiments at the Ti L 2,3 and La M 4,5 edges. As shown by the resonant enhancement at the Ti L 2,3 edge, electronic states at E F receive a dominant contribution from Ti 3d states. Both Ti and La resonance effects in the valence-band region are used to estimate the valence-band maxima at the two sides of the junction. Through a comparison with the valence-band states of the LaAlO 3 and SrTiO 3 parent compounds, we reconstruct the band diagram of the heterojunction, which is revealed to be type I (straddling gap), with a large notch of the band profile at the interface as compared with the reference insulating (3 u.c. LaAlO 3 ) interface.
Original language | English |
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Article number | 035124 |
Pages (from-to) | - |
Journal | Physical Review B (Condensed Matter and Materials Physics) |
Volume | 90 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2014 |
Keywords
- METIS-304628
- IR-91528