Experimental linear optics quantum logic

J. D. Franson, B. C. Jacobs, T. B. Pittman

Chris Sparrow, Jacques Carolan, Christopher Harrold +13 more

J. D. Franson, B. C. Jacobs, T. B. Pittman

Abstract Probabilistic quantum logic operations can be implemented using linear optical elements, additional photons (ancilla), and post‐selection based on the results of measurements made on the ancilla photons. Here we describe the experimental demonstration of several quantum logic devices of that kind, including a quantum parity check and a destructive controlled‐NOT (CNOT) gate. An experimental demonstration of feed‐forward control for use in quantum logic operations is also reported. The implementation of a conventional CNOT gate using polarizing beam splitters is described, along with a new “high‐fidelity” approach in which the logic gates always produce an output.

J. D. Franson, Michael J. Fitch, B. C. Jacobs +1 more

Quantum logic operations can be performed using linear optical elements, additional photons (ancilla), and feed-forward control based on the results of measurements on the ancilla. An experimental demonstration of several logic devices of this kind will be described, including a controlled-NOT logic gate for single photons.

Emanuel H. Knill

J. D. Franson, Michelle M. Donegan, Michael J. Fitch +2 more

Probabilistic quantum logic operations can be performed using linear optical elements and post-selection based on the results of measurements on ancilla photons. We review the results of a number of recent experiments in this area, including the demonstration of several quantum logic gates, the use of feed-forward control, a new source of single photons, and a quantum memory device for single photons. A high-fidelity approach in which the logic gates always produce an output will also be discussed.