Quantum quenches and competing orders: I. Time-dependent   Hartree-Fock+BCS theory
  We study the non-equlibrium dynamics of an electronic model of competing bond density wave order and $d$-wave superconductivity. In a time-dependent Hartree-Fock+BCS approximation, the dynamics reduces to the equations of motion of operators realizing the generators of SU(4) at each pair of momenta, $(\boldsymbol{k}, -\boldsymbol{k})$, in the Brillouin zone. We compare the results of numerical studies of our model with recent picosecond optical experiments. 
Wenbo Fu, Ling-Yan Hung, Subir Sachdev
cond-mat.supr-con cond-mat.str-el