Date/Time
Date(s) - 05/01/2005
3:30 pm - 4:30 pm

Title: Superconductivity and giant fluctuations in quantum critical metals

Speaker: Dr. Stephen Julien

Institute: University of Toronto

Location: ABB 102

Description:

The modern, quantum theory of condensed matter regards each material as a Universe unto itself, with excitations that are analogous to the electrons, positrons, photons, etc. of our everyday universe. By applying hydrostatic pressure to a material we can modify the ‘particles’ that inhabit it, creating some very peculiar worlds in which particles decay before they can propagate while the interaction between the particles becomes divergently strong. I will describe experiments on systems which we believed would show these properties but still be amenable to conventional analysis: three-dimensional metals that are on the verge of magnetic order at the absolute zero of temperature. Such magnetic ‘quantum critical’ systems are found, however, to behave even more strangely than predicted, having novel superconducting phases or strange states where giant, very slow fluctuations seem to mimic the effects of static disorder.