Generation of arbitrary quantum state in a high-Q cavity
  We present a scheme to generate arbitrary superposition of the Fock states in a high-Q cavity. This proposal is based on a sequence of laser pulses, which are tuned appropriately to control transitions on Fock state. It is shown that N laser pulses are needed to generate a pure state with a phonon number limit $N$. 
XuBo Zou, K. Pahlke and W. Mathis