Talk page

Title:
Electromagnetic response of semimetals from wavefunction geometry and topology

Speaker:
Joel Moore

Abstract:
Many topological phases have been discovered recently that do not depend on strong correlations but can be well described at the independent-electron level using concepts such as Berry’s phase and topological invariants. The next step was to figure out measurable responses generated by these wavefunction properties, and surprisingly many of the same mathematical objects that determine responses in topological phases are useful more broadly. An example in insulators is the orbital magnetoelectric polarizability. This talk focuses on (semi-)metals, where we show how a number of linear and nonlinear electromagnetic responses at low frequency, including the chiral/gyrotropic magnetic effects and some pieces of second-harmonic generation, are determined by Berry phases and orbital moments of Bloch electrons.

Link:
http://scgp.stonybrook.edu/video_portal/video.php?id=2608

Workshop:
Simons- Program: Geometry of Quantum Hall States