Details

Autor(en) / Beteiligte

• Wang, Z
• McKeown Walker, S
• Tamai, A
• Wang, Y
• Ristic, Z
• Bruno, F Y
• de la Torre, A
• Riccò, S
• Plumb, N C
• Shi, M
• Hlawenka, P
• Sánchez-Barriga, J
• Varykhalov, A
• Kim, T K
• Hoesch, M
• King, P D C
• Meevasana, W
• Diebold, U
• Mesot, J
• Moritz, B
• Devereaux, T P
• Radovic, M
• Baumberger, F

Titel

Tailoring the nature and strength of electron-phonon interactions in the SrTiO3(001) 2D electron liquid

Ist Teil von

• Nature materials, 2016-08, Vol.15 (8), p.835-839

Ort / Verlag

England

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Surfaces and interfaces offer new possibilities for tailoring the many-body interactions that dominate the electrical and thermal properties of transition metal oxides. Here, we use the prototypical two-dimensional electron liquid (2DEL) at the SrTiO3(001) surface to reveal a remarkably complex evolution of electron-phonon coupling with the tunable carrier density of this system. At low density, where superconductivity is found in the analogous 2DEL at the LaAlO3/SrTiO3 interface, our angle-resolved photoemission data show replica bands separated by 100 meV from the main bands. This is a hallmark of a coherent polaronic liquid and implies long-range coupling to a single longitudinal optical phonon branch. In the overdoped regime the preferential coupling to this branch decreases and the 2DEL undergoes a crossover to a more conventional metallic state with weaker short-range electron-phonon interaction. These results place constraints on the theoretical description of superconductivity and allow a unified understanding of the transport properties in SrTiO3-based 2DELs.