Spontaneous Symmetry Breaking and the phases of Superfluid 3He

Colloquium - Department of Physics, University of Alberta

Authors: J. A. Sauls
Department of Physics & Astronomy, Northwestern University, Evanston, IL 60208
April 6, 2018

Abstract: One of the key features of spontaneous symmetry breaking in condensed matter and quantum field theory is the emergence of new elementary quanta - phonons in crystalline solids, magnons in ferromagnets, the Higgs and gauge bosons of the Standard Model. In the latter example, the BCS theory of superconductivity played a role in the development of theories of the mass spectrum of elementary particles. I discuss the theoretical ideas of Nambu, Jona-Lasinio, Anderson and Higgs for the spectrum of Bose quanta in BCS-type theories. These ideas are realized by the discoveries of Higgs Bosons at the LHC and in superconducting matter. In the latter case I highlight the discoveries of Nambu-Goldstone and Higgs Bosons in superfluid 3He, the light isotope of Helium. The superfluid phases of 3He are also paradigms for topologically ordered quantum matter, the signatures being a spectrum of massless Majorana and Weyl particles confined on lower dimensional boundaries and interfaces. Theoretical ideas and predictions are driving a new generation of experiments to detect and and control these novel excitations.

Research supported by NSF grant DMR-1508730.

Slides: [PDF]

Colloquia and Seminars Home Physics Department Northwestern University
Last update: April 17, 2018