| We have developed and characterized the first optical-fiber-based source of deterministically split polarization-entangled pairs of photons with identical spatial-profile, temporal and polarization modes. In addition to providing insight into the fundamental and not yet fully understood phenomenon of quantum entanglement, the entanglement source is of interest for quantum communication and computing applications using the linear optic quantum computing paradigm, which requires photon pairs identical in all modes except the spatial mode of propagation, and only one photon per input spatial mode. The source was characterized using coincidence-basis tomographic reconstruction of the polarization state of photon pairs. Such characterization enabled optimization of the pair creation conditions, as well as pair propagation conditions, for the maximization of entanglement. Another set of two-photon polarization states we created were high-fidelity target pure and mixed states of various degrees of entanglement. The importance of this work was in reproducing effects of main physical processes which degrade fiber-generated polarization entanglement during fiber-optic network propagation.;We have also built one of the first quantum-optical implementations of quantum game protocols - a quantum extension of the public goods game. This protocol utilizes the source of fiber-generated entangled pairs and a modified controlled-not gate we built, to achieve higher payoff per player in a rational (self-interested) game, than the classical version of the protocol which does not utilize the entanglement source and the entangling gate. |
