SPEAKER PROFILE



Prof. Andrea Caviglia
Department of Quantum Matter Physics, University of Geneva

Switzerland

The quantum metric of electrons with spin-momentum locking

Abstract

Quantum materials are characterized by electromagnetic responses intrinsically linked to the geometry and topology of the electronic wavefunctions. These properties are encoded in the quantum metric and Berry curvature. While Berry curvature-mediated transport effects such as the anomalous and nonlinear Hall effects have been identified in several magnetic and nonmagnetic systems, observations of quantum metric-induced transport phenomena remain scarce. I will discuss the recent experimental observation that spin-momentum locking -- a general characteristic of the electronic states at surfaces and interfaces of spin-orbit coupled materials -- leads to a finite quantum metric. This metric activates a nonlinear in-plane magnetoresistance that we measure and electrically control in 111-oriented LaAlO3/SrTiO3 interfaces. These findings demonstrate the existence of quantum metric effects in a vast class of materials and provide new strategies to design functionalities based on the quantum geometry.

Bio

Andrea Caviglia joined the Department of Quantum Matter Physics at the University of Geneva in January 2022 as a full professor. Previously, his research group was based at Delft University of Technology. His current research programme focuses on synthesizing and investigating condensed matter systems with exceptional electronic properties, achieved through material design at the atomic scale. The programme centres on two key themes: oxide interface physics and controlling quantum materials with light. The team has made contributions to the field of quantum materials design, including advancements in light-induced magnetism, ultrafast strain engineering, nanoscale electrostatic control of superconductivity and exploration of topological correlated materials.