dorsal/arxiv
View SchemaDe Broglie Wavelength of a Nonlocal Four-Photon
| Authors | Philip Walther, Jian-Wei Pan, Markus Aspelmeyer, Rupert Ursin, Sara Gasparoni, Anton Zeilinger |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0312197 |
| URL | https://arxiv.org/abs/quant-ph/0312197 |
| DOI | 10.1038/nature02552 |
Abstract
Superposition is one of the most distinct features of quantum theory and has been demonstrated in numerous realizations of Young's classical double-slit interference experiment and its analogues. However, quantum entanglement - a significant coherent superposition in multiparticle systems - yields phenomena that are much richer and more interesting than anything that can be seen in a one-particle system. Among them, one important type of multi-particle experiments uses path-entangled number-states, which exhibit pure higher-order interference and allow novel applications in metrology and imaging such as quantum interferometry and spectroscopy with phase sensitivity at the Heisenberg limit or quantum lithography beyond the classical diffraction limit. Up to now, in optical implementations of such schemes lower-order interference effects would always decrease the overall performance at higher particle numbers. They have thus been limited to two photons. We overcome this limitation and demonstrate a linear-optics-based four-photon interferometer. Observation of a four-particle mode-entangled state is confirmed by interference fringes with a periodicity of one quarter of the single-photon wavelength. This scheme can readily be extended to arbitrary photon numbers and thus represents an important step towards realizable applications with entanglement-enhanced performance.
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"abstract": "Superposition is one of the most distinct features of quantum theory and has\nbeen demonstrated in numerous realizations of Young\u0027s classical double-slit\ninterference experiment and its analogues. However, quantum entanglement - a\nsignificant coherent superposition in multiparticle systems - yields phenomena\nthat are much richer and more interesting than anything that can be seen in a\none-particle system. Among them, one important type of multi-particle\nexperiments uses path-entangled number-states, which exhibit pure higher-order\ninterference and allow novel applications in metrology and imaging such as\nquantum interferometry and spectroscopy with phase sensitivity at the\nHeisenberg limit or quantum lithography beyond the classical diffraction limit.\nUp to now, in optical implementations of such schemes lower-order interference\neffects would always decrease the overall performance at higher particle\nnumbers. They have thus been limited to two photons. We overcome this\nlimitation and demonstrate a linear-optics-based four-photon interferometer.\nObservation of a four-particle mode-entangled state is confirmed by\ninterference fringes with a periodicity of one quarter of the single-photon\nwavelength. This scheme can readily be extended to arbitrary photon numbers and\nthus represents an important step towards realizable applications with\nentanglement-enhanced performance.",
"arxiv_id": "quant-ph/0312197",
"authors": [
"Philip Walther",
"Jian-Wei Pan",
"Markus Aspelmeyer",
"Rupert Ursin",
"Sara Gasparoni",
"Anton Zeilinger"
],
"categories": [
"quant-ph"
],
"doi": "10.1038/nature02552",
"title": "De Broglie Wavelength of a Nonlocal Four-Photon",
"url": "https://arxiv.org/abs/quant-ph/0312197"
},
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