Distillation of optical Fock states using atom-cavity systems

Fock states are quantized states of electromagnetic waves with diverse applications in quantum optics and quantum communication. However, the generation of arbitrary optical Fock states still remains elusive. Most Fock-state-generation proposals rely on precisely controlling the atom-cavity interactions and are experimentally challenging. We propose a scheme to distill an optical Fock state from a coherent state. A conditional phase flip with arbitrary phase is implemented between the atom and light. The conditional phase flip along with unitary rotations and measurements on the atoms enables us to distill the required Fock state. As an example, we show the distillation of Fock state $|100⟩$.