Evolution of ferromagnetism in two-dimensional electron gas of LaTiO3/SrTiO3

Abstract

Understanding, creating, and manipulating spin polarization of two-dimensional electron gases at complex oxide interfaces presents an experimental challenge. For example, despite almost a decade long research effort, the microscopic origin of ferromagnetism in LaAlO3/SrTiO3 heterojunction is still an open question. Here, by using a prototypical two-dimensional electron gas (2DEG) which emerges at the interface between band insulator SrTiO3 and antiferromagnetic Mott insulator LaTiO3 , the experiment reveals the evidence for magnetic phase separation in hole-doped Ti d1 t2g system resulting in spin-polarized 2DEG. The details of electronic and magnetic properties of the 2DEG were investigated by temperature-dependent d.c. transport, angle-dependent X-ray photoemission spectroscopy, and temperature-dependent magnetoresistance. The observation of clear hysteresis in magnetotransport at low magnetic fields implies spin-polarization from magnetic islands in the hole rich LaTiO3 near the interface. These findings emphasize the role of magnetic instabilities in doped Mott insulators thus providing another path for designing all-oxide structures relevant to spintronics applications.

References in corpus (9)

• Magnetic effects at the interface between nonmagnetic oxides
• Interface-Induced Phenomena in Magnetism
• Oxide spintronics
• Emergent properties hidden in plane view: Strong electronic correlations at oxide interfaces
• Surface magnetism of strontium titanate
• Novel photo-conducting state and its perturbation by electrostatic fields in oxide-based two-dimensional electron gas
• Evidence for charge-vortex duality at the LaAlO${}_3$/SrTiO${}_3$ interface
• A general law for electromagnetic induction
• Phase separation in doped Mott insulators

Cited by in corpus (5)

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• Epitaxial stabilization of (111)-oriented frustrated quantum pyrochlore thin films
• Metallic interfaces in a CaTiO${}_3$/LaTiO${}_3$ heterostructure
• Ferromagnetic Two-dimensional Electron Gases with Magnetic Doping and Proximity Effects
• Self-Diffusion and Structure of a Quasi Two-Dimensional, Classical Coulomb Gas Under Increasing Magnetic Field and Temperature