We present a scheme to generate entangled photons using the NV centers in
diamond. We show how the long-lived nuclear spin in diamond can mediate
entanglement between multiple photons thereby increasing the length of
entangled photon string. With the proposed scheme one could generate both
n-photon GHZ and cluster states. We present an experimental scheme realizing
the same and estimating the rate of entanglement generation both in the
presence and absence of a cavity.Comment: 4 pages, 2 figure
