2001/01/16 by Berthold-Georg Englert, Berthold‐Georg Englert, Christian Kurtsiefer +1 · 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.63.032303
published as Physical Review A, vol. 63, 2001, art. no. 032303 (10 pages) · to appear in Phys. Rev. A, 10 pages, 7 figures, 2 tables
arxiv created 2001/01/16 · openalex publication_date 2001/02/07 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Upon entangling a spatial binary alternative of a photon with its polarization, one can use single photons to study arbitrary 2-qubit states. Sending the photon through a Mach-Zehnder interferometer, equipped with sets of wave plates that change the polarization, amounts to performing a unitary transformation on the 2-qubit state. We show that any desired unitary gate can be realized by a judicious choice of the parameters of the setup and discuss a number of applications. They include the diagnosis of an unknown 2-qubit state, an optical Grover search, and the realization of a thought experiment invented by Vaidman, Aharonov, and Albert.