Dresden 2017 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
O: Fachverband Oberflächenphysik
O 76: Plasmonics and Nanooptics VII: Applications and Other Aspects
O 76.10: Talk
Wednesday, March 22, 2017, 17:15–17:30, TRE Ma
Polaronic nature of charge carriers at the LAO/STO interface — •Vladimir N. Strocov1, Claudia Cancellieri2, Adrian Husanu1, Ulrich Ashauer3, and Andrey Mishchenko4 — 1Swiss Light Source, Paul Scherrer Insitute, Switzerland — 2EMPA, Switzerland — 3University of Bern, Switzerland — 4RIKEN Center for Emergent Matter Science, Japan
2D electron system emergent at the paradigm buried oxide interface LaAlO3/SrTiO3 (LAO/STO) is explored with soft-X-ray ARPES, which combines resolution in electron energy and momentum with enhanced probing depth and chemical specificity [1]. Accentuated with resonant photoexcitation of the interface Ti3+ ions, ARPES response of the interface charge carriers resolves the manifold energy band structure of t2g-derived subbands formed in the interface quantum well. The temperature dependent peak-dip-hump spectral lineshape manifests polaronic nature of the interface electrons, where the breathing-mode LO3 phonon at 118 meV limits low-temperature mobility of the interface charge carriers, and the polar TO1 one, changing its frequency from 18 to 14 meV across the antiferrodistortive phase transition, causes a dramatic mobility drop with temperature [2]. Doping with oxygen vacancies, affecting electron-phonon coupling, opens ways to tune the interfacial mobility at oxide interfaces in view of their potential device applications.
1. V.N. Strocov et al, Synchr. Rad. News 27, N2 (2014) 31
2. C. Cancellieri et al, Nature Comm. 7 (2016) 10386