Physics Colloquium: Imaging Phase Transitions with Scanning SQUID

Abstract: 

We use a local magnetic imaging technique, scanning SQUID microscopy, to map the spatial distribution of electronic states near surfaces and interfaces. We track conductivity, superconductivity and magnetism in systems undergoing phase transitions, where the local picture is particularly meaningful. I will describe two recent findings: (1) Conduction landscape that changes dramatically near the metal to insulator transition at the 2D LaAlO3/SrTiO3 interface. (2) Non-trivial behavior of superconducting fluctuations near the superconductor to insulator transition in NbTiN. The local view allows us to investigate the way local features control the behavior.

Event Organizer: Dr. Iair Arcavi