Classification and characterization of nonequilibrium Higgs modes in unconventional superconductors

  title={Classification and characterization of nonequilibrium Higgs modes in unconventional superconductors},
  author={Lukas Schwarz and Benedikt Fauseweh and Naoto Tsuji and Nathan Cheng and Nikolaj Bittner and Holger Krull and Mona Berciu and G. S. Uhrig and Andreas P. Schnyder and Stefan Kaiser and Dirk Manske},
  journal={Nature Communications},
Recent findings of new Higgs modes in unconventional superconductors require a classification and characterization of the modes allowed by nontrivial gap symmetry. Here we develop a theory for a tailored nonequilibrium quantum quench to excite all possible oscillation symmetries of a superconducting condensate. We show that both a finite momentum transfer and quench symmetry allow for an identification of the resulting Higgs oscillations. These serve as a fingerprint for the ground state gap… 
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