2008/10/15 by Jan Soubusta, Lucie Bartůšková, Lucie Bartuskova +6 · 1 citation
Computer Science · Physics and Astronomy · #Neural Networks and Reservoir Computing #Orbital Angular Momentum in Optics #Quantum Information and Cryptography #quant-ph
paper · pdf · doi:10.1103/physreva.78.052323
7 pages, 8 figures
arxiv created 2008/10/15 · openalex publication_date 2008/11/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report on two optical realizations of the 1\ensuremath→2 asymmetric phase-covariant cloning machines for polarization states of single photons. The experimental setups combine two-photon interference and tunable polarization filtering, which enables us to control the asymmetry of the cloners. The first scheme involves a special unbalanced bulk beam splitter exhibiting different splitting ratios for vertical and horizontal polarizations, respectively. The second implemented scheme consists of a balanced fiber coupler where photon bunching occurs, followed by a free-space part with polarization filters. With this latter approach we were able to demonstrate very high cloning fidelities which are above the universal cloning limit.