Alexandre Fete

Two-dimensional quantum oscillations of the conductance at LaAlO3/SrTiO3 interfaces.

We report on a study of magnetotransport in LaAlO3 /SrTiO3 interfaces characterized by mobilities of the order of several thousands cm2/V s. We observe Shubnikov-de Haas oscillations whose period depends only on the perpendicular component of the magnetic field. This observation directly indicates the formation of a two-dimensional electron gas originating from quantum confinement at the interface. From the temperature dependence of the oscillation amplitude we extract an effective carrier mass m* ≃ 1.45 m(e). An electric field applied in the back-gate geometry increases the mobility, the carrier density, and the oscillation frequency.

Influence of the growth conditions on the LaAIO3/SrTiO3 interface electronic properties

The effects of oxygen pressure during the growth of LaAlO3 on (001) SrTiO3, and of post-deposition annealing were investigated. While little influence on the structure was observed, the transport properties were found to depend on both growth pressure and annealing. For LaAlO3 layer thicknesses between 5 and 10 unit cells and growth pressures between 10− 4 and 10−2 mbar, the LaAlO3/SrTiO3 interfaces displayed similar metallic behavior with a sharp transition to a superconducting state. At an oxygen pressure of 10− 6 mbar oxygen vacancies were clearly introduced and extended deep into the SrTiO3 crystal. These vacancies could be removed by post-deposition annealing in 0.2 bar of O2 at ~530 °C. At a growth pressure of 10− 4 mbar, the electronic properties of samples with ultra-thin LaAlO3 layers (2 to 3 unit cells thick) were found to depend markedly on the post-annealing step.

Rashba induced magnetoconductance oscillations in the LaAlO 3 -SrTiO 3 heterostructure

We report measurements of the normal state in-plane magnetoconductance in gated LaAlO

In-plane electronic confinement in superconducting LaAlO3/SrTiO3 nanostructures

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Giant oscillating thermopower at oxide interfaces

-SrTiO

Growth-induced electron mobility enhancement at the LaAlO3/SrTiO3 interface

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Large modulation of the Shubnikov?de Haas oscillations by the Rashba interaction at the LaAlO3/SrTiO3 interface

samples. As the orientation of the magnetic field changes within the plane of the interface, the signal displays periodic oscillations with respect to the angle between the field and the direction of the current. We show that in the underdoped to optimally doped range, a Fermi surface reconstruction takes place due to the Rashba spin-orbit term and that the oscillations are due to a magnetic field induced opening and closing of a gap at the

Electron confinement at the LaAlO3/SrTiO3 interface

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Weak localization and spin-orbit interaction in side-gate field effect devices at the LaAlO 3 /SrTiO 3 interface

point for those Ti out-of-plane orbitals having their band minimum close to the Fermi energy of the system.

Fabricating superconducting interfaces between artificially grown LaAlO3 and SrTiO3 thin films

We describe the transport properties of mesoscopic devices based on the two dimensional electron gas (2DEG) present at the LaAlO3/SrTiO3 interface. Bridges with lateral dimensions down to 500 nm were realized using electron beam lithography. Their detailed characterization shows that processing and confinement do not alter the transport parameters of the 2DEG. The devices exhibit superconducting behavior tunable by electric field effect. In the normal state, we measured universal conductance fluctuations, signature of phase-coherent transport in small structures. The achievement of reliable lateral confinement of the 2DEG opens the way to the realization of quantum electronic devices at the LaAlO3/SrTiO3 interface.