Graph state engineering by phase modulation of the quantum optical frequency comb

The quantum optical frequency comb (QOFC) of a single optical parametric oscillator (OPO) is a scalable platform for quantum information as a generator of large size cluster states. We show that the phase modulation of the QOFCs emitted by an OPO is a powerful graph engineering technique that can increase the topological dimension of the generated cluster state, from zero (independent EPR pairs) to one (linear cluster state), and from one to two (square-lattice cluster state), thereby allowing the creation and tailoring of universal quantum computing resources. This concept is highly compatible with integrated photonics.