Breather mode in the many-electron dynamics of semiconductor quantum   wells
  We demonstrate the existence of a novel breather mode in the self-consistent electron dynamics of a semiconductor quantum well. A non-perturbative variational method based on quantum hydrodynamics is used to determine the salient features of the electron breather mode. Numerical simulations of the time-dependent Wigner-Poisson or Hartree equations are shown to be in excellent agreement with our analytical results. For asymmetric quantum wells, a signature of the breather mode is observed in the dipole response, which can be detected by standard optical means. 
F. Haas, G. Manfredi, P. K. Shukla, and P.-A. Hervieux
cond-mat.mes-hall quant-ph