A simple model for the dynamical Casimir effect for a static mirror with   time-dependent properties
  We consider a real massless scalar field in 1+1 dimensions satisfying time-dependent Robin boundary condition at a static wall. This condition can simulate moving reflecting mirrors whose motions are determined by the time-dependence of the Robin parameter. We show that particles can be created from vacuum, characterizing in this way a dynamical Casimir effect. 
Hector O. Silva and C. Farina
hep-th quant-ph