Optical Quantum Computation And Realization Of Algorithms

A major challenge in the "big data" age is that the data size grows exponentially faster than the growth of classical computing resources. Therefore, a large number of computation tasks are intractable for classical computers. Quantum computers promise to provide an exponential speedup over their classical counterparts for certain tasks. In this dissertation, we describe first experimental demonstrations of solving entanglement-based machine learning tasks and solving linear systems of equations, both fundamental in science and engineering, on a photonics quantum computer by coherent control of multiphotons with linear optics. Further, by developing high-efficiency technique of manipulation and measurement of orbital angular momentum of photons, we realize the teleportation of multiple degrees of freedom of a single photon, which is the first experiment of multiphoton orbital angular momentum entanglement.The ability of manipulating high-dimensional vectors and multiple degrees, shown in this dissertation, combined with other techniques, may provide a useful quantum toolkit for dealing with the "big data"...