Magnetic and Superconducting Ordering at LaAlO3/SrTiO3 Interfaces

Abstract

We formulate a model for magnetic and superconducting ordering at LaAlO3/SrTiO3 interfaces containing both localized magnetic moments and itinerant electrons. Though these both originate in Ti 3d orbitals, the former may be due to electrons more tightly-bound to the interface while the latter are extended over several layers. Only the latter contribute significantly to metallic conduction and superconductivity. In our model, the interplay between the two types of electrons, which is argued to be ferromagnetic, combined with strong spin-orbit coupling of the itinerant electrons, leads to magnetic ordering. Furthermore, we propose a model for interfacial superconductivity, consisting of random superconducting grains in the bulk STO driven, via coupling to the interface conduction band, towards long-ranged or quasi-long-ranged order. Most interestingly, the magnetic order and strong spin orbit coupling can lead in this manner to unconventional interfacial superconductivity, yielding a possible realization of Majorana physics.

11 pages, 7 figures

References in corpus (8)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Majorana Fermions and a Topological Phase Transition in Semiconductor-Superconductor Heterostructures
• Magnetic effects at the interface between nonmagnetic oxides
• Multichannel Generalization of Kitaev's Majorana End States and a Practical Route to Realize Them in Thin Films
• Search for Majorana fermions in multiband semiconducting nanowires
• Theory of 2D superconductor with broken inversion symmetry
• Rashba induced magnetoconductance oscillations in the LaAlO3-SrTiO3 heterostructure
• Carrier-controlled ferromagnetism in SrTiO3

Cited by in corpus (2)

• Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces
• Anomalous Transport in Sketched Nanostructures at the LaAlO3/SrTiO3 Interface