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Casimir Effect and Interaction Between Surface Plasmons Francesco Intravaia

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Casimir Effect and Interaction Between Surface Plasmons Francesco Intravaia Casimir Effect and Interaction between Surface Plasmons Francesco Intravaia To cite this version: Francesco Intravaia. Casimir Effect and Interaction between Surface Plasmons. Physics [physics]. Université Pierre et Marie Curie - Paris VI, 2005. English. tel-00009755 HAL Id: tel-00009755 https://tel.archives-ouvertes.fr/tel-00009755 Submitted on 14 Jul 2005 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Laboratoire Kastler-Brossel Universit¶ePierre et Marie Curie Th`ese de doctorat de l'Universit¶eParis VI Sp¶ecialit¶e: Physique Quantique pr¶esent¶eepar Francesco Intravaia Pour obtenir le grade de DOCTEUR de l'UNIVERSITE¶ PARIS 6 E®et Casimir et interaction entre plasmons de surface Soutenue le 21 Juin 2005 devant le jury compos¶ede : M. Daniel BLOCH . .Rapporteur M. Jean-Michel COURTY . Examinateur M. Jacques LAFAIT . Pr¶esident du jury Mme Astrid LAMBRECHT . Directrice de th`ese M. Roberto ONOFRIO . Rapporteur M. Serge REYNAUD . Examinateur Abstract-R¶esum¶e n this thesis we discuss the influence of surface plasmons on the Casimir e®ect between two plane parallel metallic mirrors at arbitrary distances. Using the plasma model to I describe the optical response of the metal, we express the Casimir energy as a sum of contributions associated with evanescent surface plasmon modes and propagative cavity modes. In contrast to expectations, the plasmonic mode contribution is essential at all distances in order to ensure the correct result for the Casimir energy. One of the two plas- monic modes gives rise to a repulsive contribution, balancing the attractive contributions from propagating cavity modes, while both contributions taken separately are much larger than the actual value of the Casimir energy. This also suggests possibilities to tailor the sign of the Casimir force via surface plasmons. Keywords: Casimir E®ect, vacuum fluctuations, optical networks, scattering am- plitudes, hydrodynamic model, surface plasmons, logarithmic argument theorem, cavity modes, repulsive Casimir force. ans cette th`ese on discute l'influence des plasmons de surfaces sur l'e®et Casimir entre deux miroirs m¶etalliques plans et parall`eles plac¶es`aune distance arbitraire. D En utilisant le model plasma pour d¶ecrire la r¶eponse optique du m¶etal, on exprime l'¶energie de Casimir comme une somme des contributions associ¶ees aux modes ¶evanescents relatifs aux plasmons de surface et aux modes propagatifs de la cavit¶e.Contrairement `a une ce qu'on pouvait attendre, la contribution des modes plasmoniques est essentielle `a toute distance a¯n d'assurer le correct r¶esultat pour l'¶energie de Casimir. Un des deux modes plasmoniques g¶en`ere une contribution r¶epulsive qui compense la contribution at- tractive provenant des modes propagatifs de la cavit¶e, alors que les deux contributions, prises s¶epar¶ement, sont beaucoup plus importantes que la valeur r¶eelle pour l'¶energie de Casimir. Cela sugg`ere qu'il est possible d'ajuster le signe de la force de Casimir en mani- pulant les plasmons de surface. Mots-cl¶e : E®et Casimir, fluctuations du vide, r¶eseaux optiques, amplitudes de di®u- sion, mod`ele hydrodynamique, plasmons de surface, th¶eor`eme de l'argument du logarithme, modes de cavit¶e, force de Casimir r¶epulsive i ii Acknowledgements e vous avoue que j'ai longuement r¶efl¶echi `ala langue `autiliser pour les remerciements : une th`ese ¶ecrite en anglais, par un italien, dans un laboratoire fran»cais... bref, `ames J yeux ce n'¶etait pas la chose la plus ¶evidente. En¯n, ne sachant pas me d¶ecider, en demandant conseil autour de moi et au prix de me faire traiter de frimeur j'ai d¶ecid¶ede faire un petit m¶elange... Conversely to what one might naively think the PhD is not the result of only one person. Of course there is only one person who, during ¯ve months or more, spends all his time in front of a PC trying to explain something in the simplest, but not simplistic, manner he can do, trying to make a picture, a plot and so on. But this is only a little bit of the PhD period. The PhD thesis is the result of a group work where more or less all the people contribute as they can to the achievement of the ¯nal goal. Each one has brought his little, medium, or huge stone to the building and I would like to thank everybody but I think that all the manuscript pages would be not enough for this. Nevertheless, some people have played an essential role. First of all I wish to thank very much Astrid for the scienti¯c and the human support. She trusted in me even when I was not so con¯dent. This stimulated me to overcome my limits and reach results I did not guess. She took with me a lot of often unusual bets, last between them the redaction in English of the manuscript. Thank you very much Astrid! A great MERCI to Serge who supervised my work during my ¯rst year and played a crucial role in last part of it. I wish to thank him for his advices, his patience (I confess that sometimes I am very di±cult to understand) and his help even during the weekend!! I wish also to thank the remanent of my PhD board of examiners: Jacques Lafait, Jean-Michel Courty, Daniel Bloch and Roberto Onofrio. A particular thank to those last two to have been the referees of my manuscript. Grazie a Roberto per avermi sempre consigliato e sostenuto. As I said previously the PhD thesis is the result of a work of a group of persons which has its hard core in the Fluctuation and Relativity group at the Kastler-Brossel Laboratory in the Jussieu site. With Astrid and Serge this group is composed by three PhD students and by a just con¯rmed permanent member (et oui!!). During my PhD I have found in these guys real friends. Je voulais tout d'abord remercier beaucoup le plus ^ag¶ed'entre eux, Brahim (il s'av`ere purtant qu'il est m^eme plus jeune que moi ! !). Il a ¶et¶eplus que pr¶ecieux pendant toutes iii mes ann¶ees de th`ese. Il a toujours ¶et¶edisponible pour tout et j'ai pu compter sur lui `a chaque moment et pour n'importe quelle raison, scienti¯que et non. Je remercie ¶enorm¶ement R¶emy pour m'avoir support¶edans mes petites manies (tapoter sur le bureau , faire le cents pas, etc.) mais aussi et surtout pour avoir su m'¶ecouter quand j'avais besoin de parler pendant des moments di±ciles. En¯n merci aux deux derniers qui ont rejoint l'¶equipe au d¶ebut de ma derni`ere ann¶ee de th`ese : Fran»cois-Xavier (mieux connu comme FX !) et Guillaume avec lesquels on s'est entendu tout de suite super bien. Le laboratoire a ¶et¶epour moi une grande famille. Le climat amical qui y r`egne a ¶et¶e plus que b¶en¶e¯que pour mon travail. J'ai pu trouver un r¶epondant `atous les niveaux : techniciens, administratifs, chercheurs, doctorants, visiteurs, vraiment tous. Evidemment¶ c'est principalement au niveau des doctorants que j'ai tissu les liens les plus forts. Non so come ringraziare il mitico Martino che con la sua amicizia mi ha aiutato ad attraversare uno periodo molto di±cile per me. Una parsona con un cuore grande quanto una casa. Lo stesso vale per Julien (Super Juju!) che completa la piccola cricca dei dottorandi puramente teorici de la pyramide. Per quante volte l'abbia potuto disturbare non mi ha mai detto di no! Merci Juju!!! Je voulais aussi remercier the great Sylvain in Vienna, in USA et un peu partout dans le monde, et Vincent : eux aussi ont ¶et¶etoujours disponibles pour un coup de main et pleins de bonnes id¶ees. Merci beaucoup aussi `atous les autres doctorants du laboratoire ! ! Certains chercheurs en blaguant ont sugg¶er¶ed'italianiser le nom du laboratoire : La- boratorio Kastlero-Brossello, ils disent. C'est d^ua la forte composante italienne de ses membres. Tra loro Alberto, che nonostante il fatto che ti¯ Milan e che venga da Arcore (ognuno ha i suoi difetti!) `euna persona simpaticissima, e Marco, uno spettacolare toscanaccio D.O.C.. Con loro ho diviso con piacere e per molto tempo il ghetto italiano della Torre 12. Alcuni amici transalpini hanno bravato i limiti di questo territorio con il risultato che ora parlano un franco-ritale di qualit`a!Tra loro Augustin, Vincent, Aur¶elien et Charles. Ho potuto constatare che il povero Jean che pensavo si fosse salvato invece presenta purtroppo anche lui tutti i sintomi della ritalizazione. Le laboratoire a ¶et¶eun carrefour des chemins incroyable. J'ai pu rencontrer et tisser des rapports d'amiti¶eavec des personnes venant d'un peu partout. En particulier il y a eu Riccardo, Antonino, Sophie et en ¯n Estefania. Malgr¶eleur bref s¶ejour j'ai partag¶e avec eux \les joies et les douleur" d'un th¶esitif. Je suis particuli`erement reconnaissant `a Estefania et Sophie pour l'amiti¶equ'elles m'ont o®ert.
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