  We present a quantum description of photon creation via dynamical Casimir
effect based on the standard Hamiltonian formulation. The particle
representation is constructed in the expansion of field operators fixed with
the initial modes. The Hamiltonian is presented in terms of the creation and
annihilation operators with the time-varying couplings which originate from the
external properties such as an oscillating boundary or a plasma mirror of a
semiconductor slab. Some consideration is also made for the experimental
realization with a semiconductor plasma mirror.
