Colloquium on July 30, 2012

Gil Refael
California Institute of Technology

Messy magnets and dirty superfluids

Magnets and superfluids provide the simplest examples of symmetry breaking and correlations in interacting quantum systems. When disorder is thrown into the mix, particularly in low-dimensional quantum systems, novel and universal behavior often emerges. In my talk I will first explore some surprising effects of disorder in systems of non-interacting electrons, and magnetic chains. I will then focus on the superfluid-insulator transition for interacting bosons in a disordered environment. Recent research on this system has brought about a new understanding of superfluidity and its demise in low-dimensional disordered bosonic systems.