Seminars and Events
Coordinador: Rafael Jiménez-Riobóo
03 February 2020, 12:00 h. Salón de Actos
SrTiO3-based 2-dimensional electron gases for ultralow power spintronics: Has oxide electronics finally found its “killer app”?
Dr. Manuel Bibes
Unité Mixte de Physique CNRS / Thales, Université Paris-Saclay, Orsay (FRANCE)
The ever increasing power consumption of Information and Communication Technology (ICT) systems currently largely based on CMOS technology is unsustainable in the mid-term1, which is driving major ICT manufacturers and the scientific community to actively search for alternative, more energy-efficient solutions for data storage and processing. One promising approach, proposed by Intel, is the so-called MESO transistor (for MagnetoElectric-Spin-Orbit), a spin-based non-volatile device in which magnetic information is written by a magnetoelectric element and read out by a spin-orbit element through the inverse spin Hall effect (ISHE) or the inverse Edelstein effect (IEE). The IEE occurs in systems with broken inversion symmetry such as the surface of topological insulators or in two-dimensional electron gases (2DEG) displaying Rashba spin-orbit coupling. The IEE is particularly attractive because of superior spin to charge conversion efficiencies and of the higher resistance of 2DEGs compared to metals showingISHE.
In this presentation, I will show that the 2DEG that forms at the interface of SrTiO3 (STO)4with LaAlO35 or reactive metals such as Al may be exploited to interconvert spin and charge currents through the direct and inverse Edelstein effects with high efficiencies. In a first part, I will present spin to charge conversion experiments using the spin-pumping technique to inject a spin current in the 2DEG. By applying a gate voltage, we tune the position of the Fermi level in the complex multi-orbital structure of STO, which results in a strong variation of the IEE amplitude with sign changes....