Higgs mode in the quench dynamics of a confined ultracold Fermi gas in   the BCS regime
  The Higgs amplitude mode of the order parameter of an ultracold confined Fermi gas in the BCS regime after a quench of the coupling constant is analyzed theoretically. Characteristic features are a damped oscillation which at a certain transition time changes into a rather irregular dynamics. We compare the numerical solution of the full set of nonlinear equations of motion for the normal and anomalous Bogoliubov quasiparticle excitations with a linearized approximation. In doing so the transition time as well as the difference between resonant systems, i.e., systems where the Fermi energy is close to a subband minimum, and off-resonant systems can be well understood and traced back to the system and geometry parameters. 
S. Hannibal, P. Kettmann, M. D. Croitoru, A. V. Vagov, V. M. Axt, T.   Kuhn
cond-mat.quant-gas