1999/04/30 by Samuel L. Braunstein · 3 citations
Computer Science · Physics and Astronomy · #Neural Networks and Reservoir Computing #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #quant-ph
paper · pdf · doi:10.1103/physreva.71.055801
published as Phys.Rev.A71:055801,2005 · 4 pages, 3 figures, new title, removed the fat!
arxiv created 1999/05/31 · openalex publication_date 2005/05/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Using the Bloch-Messiah reduction we show that squeezing is an ``irreducible'' resource which remains invariant under transformations by linear optical elements. In particular, this gives a decomposition of any optical circuit with linear input-output relations into a linear multiport interferometer followed by a unique set of single-mode squeezers and then another multiport interferometer. Using this decomposition we derive a no-go theorem for creating superpositions of macroscopically distinct states from single-photon detection. Further, we demonstrate the equivalence between several schemes for randomly creating polarization-entangled states. Finally, we derive minimal quantum optical circuits for ideal quantum nondemolition coupling of quadrature-phase amplitudes.