Plasmon-assisted transmission of entangled photons
The state of a two-particle system is said to be entangled when its quantum-mechanical wavefunction cannot be factorized into two single-particle wavefunctions. This leads to one of the strongest counter-intuitive features of quantum mechanics, namely non-locality 1 , 2 . Experimental realization of...
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description | The state of a two-particle system is said to be entangled when its quantum-mechanical wavefunction cannot be factorized into two single-particle wavefunctions. This leads to one of the strongest counter-intuitive features of quantum mechanics, namely non-locality
1
,
2
. Experimental realization of quantum entanglement is relatively easy for photons; a starting photon can spontaneously split into a pair of entangled photons inside a nonlinear crystal. Here we investigate the effects of nanostructured metal optical elements
3
on the properties of entangled photons. To this end, we place optically thick metal films perforated with a periodic array of subwavelength holes in the paths of the two entangled photons. Such arrays convert photons into surface-plasmon waves—optically excited compressive charge density waves—which tunnel through the holes before reradiating as photons at the far side
4
,
5
,
6
,
7
. We address the question of whether the entanglement survives such a conversion process. Our coincidence counting measurements show that it does, so demonstrating that the surface plasmons have a true quantum nature. Focusing one of the photon beams on its array reduces the quality of the entanglement. The propagation of the surface plasmons makes the array effectively act as a ‘which way’ detector. |
doi_str_mv | 10.1038/nature00869 |
format | Article |
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1
,
2
. Experimental realization of quantum entanglement is relatively easy for photons; a starting photon can spontaneously split into a pair of entangled photons inside a nonlinear crystal. Here we investigate the effects of nanostructured metal optical elements
3
on the properties of entangled photons. To this end, we place optically thick metal films perforated with a periodic array of subwavelength holes in the paths of the two entangled photons. Such arrays convert photons into surface-plasmon waves—optically excited compressive charge density waves—which tunnel through the holes before reradiating as photons at the far side
4
,
5
,
6
,
7
. We address the question of whether the entanglement survives such a conversion process. Our coincidence counting measurements show that it does, so demonstrating that the surface plasmons have a true quantum nature. Focusing one of the photon beams on its array reduces the quality of the entanglement. The propagation of the surface plasmons makes the array effectively act as a ‘which way’ detector.</description><identifier>ISSN: 0028-0836</identifier><identifier>EISSN: 1476-4687</identifier><identifier>DOI: 10.1038/nature00869</identifier><identifier>PMID: 12124618</identifier><identifier>CODEN: NATUAS</identifier><language>eng</language><publisher>London: Nature Publishing Group UK</publisher><subject>Atoms & subatomic particles ; Classical and quantum physics: mechanics and fields ; Exact sciences and technology ; Foundations, theory of measurement, miscellaneous theories (including aharonov-bohm effect, bell inequalities, berry's phase) ; Fundamental areas of phenomenology (including applications) ; Humanities and Social Sciences ; letter ; multidisciplinary ; Nonclassical field states; squeezed, antibunched and sub-poissonian states; operational definitions of the phase of the field; phase measurements ; Optics ; Particle physics ; Physics ; Quantum mechanics ; Quantum optics ; Quantum theory ; Science ; Science (multidisciplinary)</subject><ispartof>Nature (London), 2002-07, Vol.418 (6895), p.304-306</ispartof><rights>Macmillan Magazines Ltd. 2002</rights><rights>2002 INIST-CNRS</rights><rights>COPYRIGHT 2002 Nature Publishing Group</rights><rights>Copyright Macmillan Journals Ltd. Jul 18, 2002</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c650t-37084f5d1de0685b6f6aa94f0ba6e28be87a55cc6c9f17bfa2ba2f28ac280d5a3</citedby><cites>FETCH-LOGICAL-c650t-37084f5d1de0685b6f6aa94f0ba6e28be87a55cc6c9f17bfa2ba2f28ac280d5a3</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://link.springer.com/content/pdf/10.1038/nature00869$$EPDF$$P50$$Gspringer$$H</linktopdf><linktohtml>$$Uhttps://link.springer.com/10.1038/nature00869$$EHTML$$P50$$Gspringer$$H</linktohtml><link.rule.ids>314,776,780,27903,27904,41467,42536,51297</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=13781183$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/12124618$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Altewischer, E.</creatorcontrib><creatorcontrib>van Exter, M. P.</creatorcontrib><creatorcontrib>Woerdman, J. P.</creatorcontrib><title>Plasmon-assisted transmission of entangled photons</title><title>Nature (London)</title><addtitle>Nature</addtitle><addtitle>Nature</addtitle><description>The state of a two-particle system is said to be entangled when its quantum-mechanical wavefunction cannot be factorized into two single-particle wavefunctions. This leads to one of the strongest counter-intuitive features of quantum mechanics, namely non-locality
1
,
2
. Experimental realization of quantum entanglement is relatively easy for photons; a starting photon can spontaneously split into a pair of entangled photons inside a nonlinear crystal. Here we investigate the effects of nanostructured metal optical elements
3
on the properties of entangled photons. To this end, we place optically thick metal films perforated with a periodic array of subwavelength holes in the paths of the two entangled photons. Such arrays convert photons into surface-plasmon waves—optically excited compressive charge density waves—which tunnel through the holes before reradiating as photons at the far side
4
,
5
,
6
,
7
. We address the question of whether the entanglement survives such a conversion process. Our coincidence counting measurements show that it does, so demonstrating that the surface plasmons have a true quantum nature. Focusing one of the photon beams on its array reduces the quality of the entanglement. The propagation of the surface plasmons makes the array effectively act as a ‘which way’ detector.</description><subject>Atoms & subatomic particles</subject><subject>Classical and quantum physics: mechanics and fields</subject><subject>Exact sciences and technology</subject><subject>Foundations, theory of measurement, miscellaneous theories (including aharonov-bohm effect, bell inequalities, berry's phase)</subject><subject>Fundamental areas of phenomenology (including applications)</subject><subject>Humanities and Social Sciences</subject><subject>letter</subject><subject>multidisciplinary</subject><subject>Nonclassical field states; squeezed, antibunched and sub-poissonian states; operational definitions of the phase of the field; phase measurements</subject><subject>Optics</subject><subject>Particle physics</subject><subject>Physics</subject><subject>Quantum mechanics</subject><subject>Quantum optics</subject><subject>Quantum theory</subject><subject>Science</subject><subject>Science (multidisciplinary)</subject><issn>0028-0836</issn><issn>1476-4687</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2002</creationdate><recordtype>article</recordtype><sourceid>8G5</sourceid><sourceid>BEC</sourceid><sourceid>BENPR</sourceid><sourceid>GUQSH</sourceid><sourceid>M2O</sourceid><recordid>eNqF0t2L1DAQAPAgireuPvkui3CCaM9J2nz0cVn8ODhU9MTHME2T2qNN9pIW9L83sgt7KyuSh5DML5NkGEKeUrigUKo3Hqc5WgAl6ntkQSspikooeZ8sAJgqQJXijDxK6QYAOJXVQ3JGGWWVoGpB2OcB0xh8gSn1abLtaoro09jnZfCr4FbWT-i7IUe2P8IUfHpMHjgckn2yn5fk27u315sPxdWn95eb9VVhBIepKCWoyvGWthaE4o1wArGuHDQoLFONVRI5N0aY2lHZOGQNMscUGqag5VguyYtd3m0Mt7NNk86vMnYY0NswJy1pzRjn5X8hk6Kkda7Dkjz_C96EOfr8Cc2g4gCVkhkVO9ThYHXvXcgVMZ31NuIQvHV93l5TJXnF6xIOSY-82fa3-i66OIHyaO3Ym5NZXx4dyGayP6cO55T05dcvx_bVv-36-vvm40ltYkgpWqe3sR8x_tIU9J-G0ncaKutn-5LNzWjbg913UAbne4DJ4OBy95g-HVwpFc0su9c7l3LIdzYean_q3t-84t7A</recordid><startdate>20020718</startdate><enddate>20020718</enddate><creator>Altewischer, E.</creator><creator>van Exter, M. 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Academic</collection><jtitle>Nature (London)</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Altewischer, E.</au><au>van Exter, M. P.</au><au>Woerdman, J. P.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Plasmon-assisted transmission of entangled photons</atitle><jtitle>Nature (London)</jtitle><stitle>Nature</stitle><addtitle>Nature</addtitle><date>2002-07-18</date><risdate>2002</risdate><volume>418</volume><issue>6895</issue><spage>304</spage><epage>306</epage><pages>304-306</pages><issn>0028-0836</issn><eissn>1476-4687</eissn><coden>NATUAS</coden><abstract>The state of a two-particle system is said to be entangled when its quantum-mechanical wavefunction cannot be factorized into two single-particle wavefunctions. This leads to one of the strongest counter-intuitive features of quantum mechanics, namely non-locality
1
,
2
. Experimental realization of quantum entanglement is relatively easy for photons; a starting photon can spontaneously split into a pair of entangled photons inside a nonlinear crystal. Here we investigate the effects of nanostructured metal optical elements
3
on the properties of entangled photons. To this end, we place optically thick metal films perforated with a periodic array of subwavelength holes in the paths of the two entangled photons. Such arrays convert photons into surface-plasmon waves—optically excited compressive charge density waves—which tunnel through the holes before reradiating as photons at the far side
4
,
5
,
6
,
7
. We address the question of whether the entanglement survives such a conversion process. Our coincidence counting measurements show that it does, so demonstrating that the surface plasmons have a true quantum nature. Focusing one of the photon beams on its array reduces the quality of the entanglement. The propagation of the surface plasmons makes the array effectively act as a ‘which way’ detector.</abstract><cop>London</cop><pub>Nature Publishing Group UK</pub><pmid>12124618</pmid><doi>10.1038/nature00869</doi><tpages>3</tpages></addata></record> |
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subjects | Atoms & subatomic particles Classical and quantum physics: mechanics and fields Exact sciences and technology Foundations, theory of measurement, miscellaneous theories (including aharonov-bohm effect, bell inequalities, berry's phase) Fundamental areas of phenomenology (including applications) Humanities and Social Sciences letter multidisciplinary Nonclassical field states squeezed, antibunched and sub-poissonian states operational definitions of the phase of the field phase measurements Optics Particle physics Physics Quantum mechanics Quantum optics Quantum theory Science Science (multidisciplinary) |
title | Plasmon-assisted transmission of entangled photons |
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