Despite several attempts, the intimate electronic structure of two-dimensional electron systems buried at the interface between LaAlO3 and SrTiO3 still remains to be experimentally revealed. Here, we investigate the transport properties of a high-mobility quasi-two-dimensional electron gas at this interface under high magnetic field (55 T) and provide new insights for electronic band structure by analyzing the Shubnikov-de Haas oscillations. Interestingly, the quantum oscillations are not 1/B-periodic and produce a highly non-linear Landau plot (Landau level index versus 1/B). Among possible scenarios, the Roth-Gao-Niu equation provides a natural explanation for 1/B-aperiodic oscillations in relation with the magnetic response functions of the system. Overall, the magneto-transport data are discussed in light of high-resolution scanning transmission electron microscopy analysis of the interface as well as calculations from density functional theory.
@article{arxiv.1903.03038,
title = {Aperiodic quantum oscillations in the two-dimensional electron gas at the LaAlO3/SrTiO3 interface},
author = {Km Rubi and Julien Gosteau and Raphaël Serra and Kun Han and Shengwei Zeng and Zhen Huang and Etienne Snoeck and Rémi Arras and Benedicte Warot-Fonrose and Ariando and Michel Goiran and Walter Escoffier},
journal= {arXiv preprint arXiv:1903.03038},
year = {2020}
}