2007/04/05 by Hugo Cable, Jonathan P. Dowling · 1 citation
Computer Science · Physics and Astronomy · #Computer science #Optics #Orbital Angular Momentum in Optics #Path (computing) #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum entanglement #Quantum mechanics #Quantum optics #Statistical physics #quant-ph
paper · pdf · doi:10.1103/physrevlett.99.163604
published as Phys. Rev. Lett. 99, 163604 (2007)
arxiv created 2007/04/05 · openalex publication_date 2007/10/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We show how an idealized measurement procedure can condense photons from two modes into one and how, by feeding forward the results of the measurement, it is possible to generate efficiently superposition states commonly called N00N states. For the basic procedure sources of number states leak onto a beam splitter, and the output ports are monitored by photodetectors. We find that detecting a fixed fraction of the input at one output port suffices to direct the remainder to the same port, with high probability, however large the initial state. When instead photons are detected at both ports, macroscopic quantum superposition states are produced. We describe a linear-optical circuit for making the components of such a state orthogonal, and another to convert the output to a N00N state. Our approach scales exponentially better than existing proposals. Important applications include quantum imaging and metrology.