Speed-of-light limitations in passive linear media
We prove that well-known speed-of-light restrictions on electromagnetic energy velocity can be extended to a new level of generality, encompassing even nonlocal chiral media in periodic geometries, while at the same time weakening the underlying assumptions to only passivity and linearity of the med...
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| Format: | Article |
| Language: | English |
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American Physical Society
2014
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| Online Access: | http://hdl.handle.net/1721.1/89192 https://orcid.org/0000-0001-7327-4967 https://orcid.org/0000-0001-5994-0396 |
| _version_ | 1826207389542514688 |
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| author | Welters, Aaron Johnson, Steven G. Avniel, Yehuda B. |
| author2 | Massachusetts Institute of Technology. Department of Mathematics |
| author_facet | Massachusetts Institute of Technology. Department of Mathematics Welters, Aaron Johnson, Steven G. Avniel, Yehuda B. |
| author_sort | Welters, Aaron |
| collection | MIT |
| description | We prove that well-known speed-of-light restrictions on electromagnetic energy velocity can be extended to a new level of generality, encompassing even nonlocal chiral media in periodic geometries, while at the same time weakening the underlying assumptions to only passivity and linearity of the medium (either with a transparency window or with dissipation). As was also shown by other authors under more limiting assumptions, passivity alone is sufficient to guarantee causality and positivity of the energy density (with no thermodynamic assumptions). Our proof is general enough to include a very broad range of material properties, including anisotropy, bianisotropy (chirality), nonlocality, dispersion, periodicity, and even delta functions or similar generalized functions. We also show that the “dynamical energy density” used by some previous authors in dissipative media reduces to the standard Brillouin formula for dispersive energy density in a transparency window. The results in this paper are proved by exploiting deep results from linear-response theory, harmonic analysis, and functional analysis that had previously not been brought together in the context of electrodynamics. |
| first_indexed | 2024-09-23T13:48:33Z |
| format | Article |
| id | mit-1721.1/89192 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T13:48:33Z |
| publishDate | 2014 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/891922022-10-01T17:17:49Z Speed-of-light limitations in passive linear media Welters, Aaron Johnson, Steven G. Avniel, Yehuda B. Massachusetts Institute of Technology. Department of Mathematics Welters, Aaron Avniel, Yehuda B. Johnson, Steven G. We prove that well-known speed-of-light restrictions on electromagnetic energy velocity can be extended to a new level of generality, encompassing even nonlocal chiral media in periodic geometries, while at the same time weakening the underlying assumptions to only passivity and linearity of the medium (either with a transparency window or with dissipation). As was also shown by other authors under more limiting assumptions, passivity alone is sufficient to guarantee causality and positivity of the energy density (with no thermodynamic assumptions). Our proof is general enough to include a very broad range of material properties, including anisotropy, bianisotropy (chirality), nonlocality, dispersion, periodicity, and even delta functions or similar generalized functions. We also show that the “dynamical energy density” used by some previous authors in dissipative media reduces to the standard Brillouin formula for dispersive energy density in a transparency window. The results in this paper are proved by exploiting deep results from linear-response theory, harmonic analysis, and functional analysis that had previously not been brought together in the context of electrodynamics. Massachusetts Institute of Technology. Institute for Soldier Nanotechnologies (Grant W911NF-07-D0004) 2014-09-05T13:19:53Z 2014-09-05T13:19:53Z 2014-08 2014-05 2014-08-28T18:49:06Z Article http://purl.org/eprint/type/JournalArticle 1050-2947 1094-1622 http://hdl.handle.net/1721.1/89192 Welters, Aaron, Yehuda Aviel, and Steven G. Johnson. "Speed-of-light limitations in passive linear media." Phys. Rev. A 90, 023847 (August 2014). © 2014 American Physical Society https://orcid.org/0000-0001-7327-4967 https://orcid.org/0000-0001-5994-0396 en http://dx.doi.org/10.1103/PhysRevA.90.023847 Physical Review A Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. American Physical Society application/pdf American Physical Society American Physical Society |
| spellingShingle | Welters, Aaron Johnson, Steven G. Avniel, Yehuda B. Speed-of-light limitations in passive linear media |
| title | Speed-of-light limitations in passive linear media |
| title_full | Speed-of-light limitations in passive linear media |
| title_fullStr | Speed-of-light limitations in passive linear media |
| title_full_unstemmed | Speed-of-light limitations in passive linear media |
| title_short | Speed-of-light limitations in passive linear media |
| title_sort | speed of light limitations in passive linear media |
| url | http://hdl.handle.net/1721.1/89192 https://orcid.org/0000-0001-7327-4967 https://orcid.org/0000-0001-5994-0396 |
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