2018/11/02 by Chunhai Yin, Yin, Chunhai, Dileep Krishnan +7
Materials Science · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Electronic and Structural Properties of Oxides #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.1811.00953
openalex publication_date 2018/11/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report on the fabrication of conducting interfaces between LaAlO3 and SrTiO3 by 90o off-axis sputtering in an Ar atmosphere. At a growth pressure of 0.04 mbar the interface is metallic, with a carrier density of the order of 1013 cm-2 at 3 K. By increasing the growth pressure, we observe an increase of the out-of-plane lattice constants of the LaAlO3 films while the in-plane lattice constants do not change. Also, the low-temperature sheet resistance increases with increasing growth pressure, leading to an insulating interface when the growth pressure reaches 0.10 mbar. We attribute the structural variations to an increase of the La/Al ratio, which also explains the transition from metallic behavior to insulating behavior of the interfaces. Our research emphasizes the key role of the cation stoichiometry of LaAlO3 in the formation of the conducting interface, and also the control which is furnished by the Ar pressure in the growth process.