Tuesday, Nov 1st: Physics Colloquium - Topological Line Defects: New Windows into Electron Fractionalization in Quantum Matter

Event Date: 

Tuesday, November 1, 2016 - 4:00pm

Event Location: 

  • BROIDA ROOM 1640

The discovery of the fractional quantum Hall (FQH) effect in 1982 showed that there exist phases of matter confined to two spatial dimensions that exhibit electron fractionalization. In these states, the electron fractionalizes at low energies into emergent quasiparticle excitations, each possessing fractional electric charge and fractional quantum statistics. In this talk, I will describe a class of topological line defects that can occur in fractionalized phases of matter. These include topological interfaces in quantum spin liquids, where electrons can coherently leave their charge, spin, and even Fermi statistics behind as they propagate across the interface. In another class of topological line defect in FQH states, charge 2e/3 quasiparticles can condense, giving rise to a type of fractional superconductivity. This fractional charge condensation gives rise to topologically protected ground state degeneracies in the energy spectrum, which are robust to environmental perturbations. These ideas provide a number of potential new probes of electron fractionalization in quantum matter.

Maissam Barkeshli