Center for Artificial Low Dimensional Electronic Systems

“From Higgs oscillations to Higgs spectroscopy”

Dr. Dirk Manske

October 21(Mon) - October 21(Mon), 2019

14:00

Seminar Room #512, Hogil Kim Memoral Bldg.

In physical systems involving Fermions there exists a long list of analogies between high energy physics and condensed matter systems. In bosonic systems, however, the Higgs mechanism in superconductors, i.e. the Meissner effect, was the only analogy so far. With the recent development of THz lasers this has been changed. In general, time-resolved pump-probe experiments attracted great interest, since they allow to detecting hidden states and they provide new information on the underlying dynamics in solids in real time. With the observation of Higgs oscillations in superconductors it is now possible to investigate the superconducting order parameter, and thus the ground state, directly. We have established a theory for Higgs oscillations (and the Higgs mode in general) in superconductors in non-equilibrium after a quantum quench, for example in a THz pump-probe experiment. In this tutorial I describe how to use various methods we have developed in order to calculate the optical response and the ARPES spectrum of conventional and unconventional superconductors in a time-resolved experiment. By comparison with analytical calculations we now have a microscopic understanding of the Higgs mode in superconductors. In analogy to phonon spectroscopy, I demonstrate how Higgs oscillations allow for a complete characterization of the superconducting gap function even for new or unknown superconductors.