Magnetization generation and giant nonlinear transport at symmetry-engineered interfaces.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41513638.
- Also identified by DOI 10.1038/s41467-025-66149-1 and PMC identifier 12796300.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Interfaces in heterostructures possess inherent inversion asymmetry and display diverse physical effects, however, the pristine in-plane mirror symmetries of the constituent layers are usually preserved at the interface. On-demand manipulation of these symmetries remains challenging. Here, we demonstrate a strategy to control the in-plane mirror symmetries of interfaces by engineering the crystallographic orientation of heterostructures. We design a workhorse system with a new orientation, i.e., the LaAlO<sub>3</sub>/SrTiO<sub>3</sub> heterostructure with metallic interfaces in the (112)-plane. Such a high index orientation leads to the breaking of all the pristine mirror symmetries except the mirror plane perpendicular to the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mo>[</mo> <mrow><mn>1</mn> <mover><mrow><mn>1</mn></mrow> <mo>¯</mo></mover> <mn>0</mn></mrow> <mo>]</mo></mrow> </math> direction ( <math xmlns="http://www.w3.org/1998/Math/MathML"> <msub><mrow><mi>M</mi></mrow> <mrow><mrow><mo>[</mo> <mrow><mn>1</mn> <mover><mrow><mn>1</mn></mrow> <mo>¯</mo></mover> <mn>0</mn></mrow> <mo>]</mo></mrow> </mrow> </msub> </math> ), resulting in the C<sub>s</sub> point symmetry with a metallic conduction. Consequently, this interface exhibits a giant nonlinear Hall effect characterized by a large Berry curvature dipole, a circular photogalvanic effect, and current-induced out-of-plane magnetization, all functional at room temperature. The magnitude of the nonlinear Hall effect rivals the Weyl and Dirac systems. Our work establishes a new strategy in exploring emerging electronic properties with nontrivial quantum geometry by designing the interface symmetry.