Oxygen-vacancy clustering and pseudogap behaviour at LaAlO3/SrTiO3 interface

Abstract

The 2DEG at the LaAlO3/SrTiO3 interface promises to add a new dimension to emerging electronic devices due to its high tunability. Defects in the form of Oxygen vacancies in titanate surfaces and interfaces, on the other hand, play a key role in the emergence of novel phases. Based on an effective model, we study the influence of Oxygen vacancies on superconductivity and ferromagnetism at LaAlO3/SrTiO3 interface. Using the Bogoliubov-de Gennes formulation in conjunction with Monte-Carlo simulation, we find a clustering of the Oxygen vacancies at the interface that favours formation of coexisting ferromagnetic puddles spatially separated from superconductivity. We also find a carrier freeze-out at low temperatures, observed experimentally in wide-variety of samples. Sufficiently large amount of Oxygen vacancy leads to pseudo-gap like behaviour in the superconducting state.

5 pages, 5 figures

References in corpus (6)

• Magnetic effects at the interface between nonmagnetic oxides
• Electric Field Control of the LaAlO${}_3$/SrTiO${}_3$ Interface Ground State
• High Mobility in LaAlO3/SrTiO3 Heterostructures: Origin, Dimensionality and Perspectives
• Origin of charge density at LaAlO3-on-SrTiO3 hetero-interfaces; possibility of intrinsic doping
• Polar catastrophe and electronic reconstructions at the LaAlO3/SrTiO3 interface: evidence from optical second harmonic generation
• Emerging magnetism and electronic phase separation at titanate interfaces

Cited by in corpus (7)

• Physics of SrTiO${}_3$-based heterostructures and nanostructures: a review
• Electronic phase separation at LaAlO3/SrTiO3 interfaces tunable by oxygen deficiency
• Multi-band theory of superconductivity at the LaAlO${}_3$/SrTiO${}_3$ interface
• Observation of transient superconductivity at the LaAlO${}_3$/SrTiO${}_3$ interface
• Anomalous transport near the Lifshitz transition at the LaAlO${}_3$/SrTiO${}_3$ interface
• Effect of oxygen vacancy on structural, electronic and magnetic properties of La-based oxide interfaces
• Effect of spin-orbit interaction on the vortex dynamics in LaAlO${}_3$/SrTiO${}_3$ interfaces near the superconducting transition