dorsal/arxiv
View SchemaUniversal unitary gate for single-photon 2-qubit states
| Authors | Berthold-Georg Englert, Christian Kurtsiefer, Harald Weinfurter |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0101064 |
| URL | https://arxiv.org/abs/quant-ph/0101064 |
| DOI | 10.1103/PhysRevA.63.032303 |
| Journal | Physical Review A, vol. 63, 2001, art. no. 032303 (10 pages) |
Abstract
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 set-up 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.
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"abstract": "Upon entangling a spatial binary alternative of a photon with its\npolarization, one can use single photons to study arbitrary 2-qubit states.\nSending the photon through a Mach-Zehnder interferometer, equipped with sets of\nwave plates that change the polarization, amounts to performing a unitary\ntransformation on the 2-qubit state. We show that any desired unitary gate can\nbe realized by a judicious choice of the parameters of the set-up and discuss a\nnumber of applications. They include the diagnosis of an unknown 2-qubit state,\nan optical Grover search, and the realization of a thought experiment invented\nby Vaidman, Aharonov, and Albert.",
"arxiv_id": "quant-ph/0101064",
"authors": [
"Berthold-Georg Englert",
"Christian Kurtsiefer",
"Harald Weinfurter"
],
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"quant-ph"
],
"doi": "10.1103/PhysRevA.63.032303",
"journal_ref": "Physical Review A, vol. 63, 2001, art. no. 032303 (10 pages)",
"title": "Universal unitary gate for single-photon 2-qubit states",
"url": "https://arxiv.org/abs/quant-ph/0101064"
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