Van der Waals colloquium by prof.dr. Beena Kalisky from the Bar Ilan University (Israel) on "Probing Quantum Materials using Scanning SQUID Microscopy". Beena’s lab develops and uses sensitive, local, non-invasive magnetic probes to study superconductivity, magnetism and biomagnetism at small length scales down to the nanoscale.

Abstract
Competition or cooperation between different electronic orders with similar energy scales often gives rise to new or unexpected behaviors. Detecting traces of such orders requires versatile probes, which can probe different aspects of the system, such as conductivity, superconductivity and magnetism. In my talk, I will describe two systems where our local view uncovered surprising mesoscopic effects. One is an oxide interface, where we imaged the current flow close to a metal-to-insulator transition. We found that the critical behavior is controlled by the structure rather than by universal scaling laws. The other system is a van-der Waals material in which we found a hidden magnetic phase, revealed by a spontaneous vortices hosted by the superconductor. Overall, our results highlight the power of scanning SQUID microscopy in probing the properties of quantum materials and providing local insights into their behavior.

The Joan van der Waals colloquium is an ongoing bi-weekly lecture series, organized by LION. As all speakers are instructed to give an accessible lecture for everyone, these lectures aid in getting a broader view of physics. Each colloquium is preceded by an opening act: a PhD student or postdoc from LION and a different field than the invited speaker, to give a 10-min presentation. After the colloquium, there is a chance to meet your colleagues and participate in discussions at the borrel. More information can be found here.