Spin and orbital Edelstein effects in a two-dimensional electron gas: Theory and application to SrTiO 3 interfaces

Annika Johansson , Börge Göbel , Jürgen Henk , M. Bibes (1) , Ingrid Mertig

1 Laboratoire Albert Fert (ex-UMPhy Unité mixte de physique CNRS/Thales)

The Edelstein effect produces a homogeneous magnetization in nonmagnetic materials with broken inversion symmetry which is generated and tuned exclusively electrically. Often the spin Edelstein effect-that is, a spin density in response to an applied electric field-is considered. In this paper we report on the electrically induced magnetization that comprises contributions from the spin and the orbital moments. Our theory for these spin and orbital Edelstein effects is applied to the topologically nontrivial two-dimensional electron gas at SrTiO 3 interfaces. In this particular system the orbital Edelstein effect exceeds the spin Edelstein effect by more than one order of magnitude. This finding is explained mainly by orbital moments of different magnitude in the Rashba-like split band pairs, while the spin moments are of almost equal magnitude.

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Annika Johansson, Börge Göbel, Jürgen Henk, M. Bibes, Ingrid Mertig. Spin and orbital Edelstein effects in a two-dimensional electron gas: Theory and application to SrTiO 3 interfaces. Physical Review Research, 2021, 3 (1), ⟨10.1103/PhysRevResearch.3.013275⟩. ⟨hal-03441675⟩