Tamm plasmon Photonic Crystals : from Bandgap Engineering to Defect Cavity

We report for the first time the bandgap engineering of Tamm plasmon photonic crystals - Tamm plasmon structures of which the metalic layer is periodically patterned into lattice of subwavelength period. By adopting a double period design, we evidenced experimentally a complete photonic bandgap up to $150\,nm$ in the telecom range. Moreover, such design offers a great flexibility to tailor on-demand, and independently, the band-gap size from $30\,nm$ to $150\,nm$ and its spectral position within $50\,nm$. Finally, by implementing a defect cavity within the Tamm plasmon photonic crystal, an ultimate cavity of $1.6\mu m$ supporting a single highly confined Tamm mode is experimentally demonstrated. All experimental results are in perfect agreement with numerical calculations. Our results suggests the possibility to engineer novel band dispersion with surface modes of hybrid metalic/dielectric structures, thus open the way to Tamm plasmon towards applications in topological photonics, metamaterials and parity symmetry physics

Laser à semiconducteur en cavité verticale étendue émettant à 1550 nm et perspectives pour la génération d'impulsions brèves

Les OP-VECSELs (Optically Pumped Vertical External Cavity Semiconductor Lasers) sont des sources permettant d'obtenir des faisceaux circulaires de bonne qualité et de puissance élevée. De plus, la cavité externe permet d'envisager la réalisation de sources impulsionnelles par l'insertion d'un miroir à absorbant saturable (SESAM) dans la cavité et la mise en place d'un régime de blocage de modes passif. Ce travail de thèse a porté sur la réalisation et l'étude des OP-VECSEL, des SESAMs et des cavités optiques adaptés à la réalisation d'une source impulsionnelle à l,55 [mu]m. Le cœur de ce travail de thèse a consisté en la conception, la caractérisation, et l'obtention du fonctionnement laser en continu d'OP-VECSELs réalisés monolithiquement sur InP. La principale difficulté pour l'obtention de l'effet laser en continu a été la gestion de l'échauffement, particulièrement important lors du pompage optique des matériaux à l'accord de maille sur InP. L'effet laser à 1,55 [mu]m en pompage continu à température ambiante a cependant été obtenu, avec un seuil de 6 kW/cm^2, et une puissance de sortie de 4 mW à OʿC. Ce résultat est une première pour une structure OP- VECSEL monolithique sur InP émettant à 1,55 [mu]m. La réalisation d'une source impulsionnelle nécessite l'amélioration des propriétés thermiques des OP-VECSELs, et nous proposons de nouvelles structures satisfaisant à cette contrainte. La génération d'impulsions brèves à haut débit nécessite l'accélération de la dynamique de fonctionnement des SESAMs. Pour ce faire, nous proposons une méthode originale, consistant à placer le puits quantique jouant le rôle d'absorbant saturable très près de la surface du composant, pour bénéficier des recombinaisons rapides des porteurs sur les états de surface. Nous proposons également des configurations de cavités optiques compactes adaptées à l'obtention d'impulsions à un débit supérieur à 2 GHz.Optically-Pumped Vertical-External-Cavity Semiconductor-Lasers (OP-VECSELs) present high power circular diffraction limited output beams. Moreover, the external cavity allows the realization of passively modelocked pulsed sources by inserting a semiconductor saturable absorber mirror (SESAM) in the cavity. This work consisted in the realization and the study of OP- VECSELs, SESAMs and optical cavities for the obtention of a short pulse source at 1.55 [mu]m. The main part of this work was the design, the characterization, and the obtention of continuous wave (CW) lasing operation of monolithically grown OP-VECSELs on InP. The major difficulty for the obtention of CW lasing operation is due to the low thermal conductivity of the materials lattice matched to InP, leading to an important heating of the devices during CW optical pumping. Despite of these difficulties, a proper design of the structures allowed the obtention of room temperature CW 1asing operation, with a lasing threshold of 6 kW/cm^2, and an output power as high as 4 mW at 0ʿC. This result is at the state of the art of 1.55 [mu]m monolithically grown OP-VECSELs lattice matched to InP. However, we show that the realization of a modelocked source implies a reduction of the thermal resistivity of the OP-VECSELs, and we thus propose non-monolithical devices matching this condition. High bit rate pulse generation implies the acceleration of the SESAM dynamics. We thus propose an original SESAM configuration where the quantum well (acting as a saturable absorber) is grown very close to the surface of the device. This enhances the rapid recombination of the charge carriers on the surface states of the SESAMs. We also propose configurations of compact optical cavities compatible with the obtention of high bit rate pulses (> 2 GHz).ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF

Short time investigation of the neurospora kinesin step

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Leakage interferences applied to surface plasmon analysis

International audienceWe report the experimental combination of leakage radiation microscopy with a Young slit experiment to address the spatial coherence properties of surface waves. We applied this method to measurements of surface plasmon polaritons (SPPs). The relationship between the spatial decay and interference contrast allows us to extract the degree of coherence. In a second step, we investigate the coherence properties of the plasmon in the weak coupling regime between fluorophores and metallic surfaces. Finally, a method is proposed to extract the propagation length of SPPs in a large variety of systems

Influence of surface plasmon propagation on leakage radiation microscopy imaging

International audienceWe study in this Letter, the effect of the surface plasmon (SP) propagation and coherence on the images obtained by leakage radiation microscopy. The studied system is a set of nanocrystals deposited on a thin silver film supporting surface plasmon modes. More than 70% of the emission in this typical system comes from non-local emission. The diameter of the influence circle around the detection point is of the order of magnitude of the plasmon propagation length. We also present an original method to measure the propagation length (L-spp) of surface plasmons in complex systems by a two Young's slits experiment. This method can be useful for complex systems with a very short propagation length

Active control of radiation beaming from Tamm nanostructures by optical microscopy

International audienceActive control of the radiation orientation (beaming) of a metallic antenna has been reported by various methods, where the antenna excitation position was tuned with a typical 50 nm precision by a near-field tip or an electron-beam. Here we use optical microscopy to excite and analyze the fluorescence of a layer of nanocrystals embedded in an optical Tamm state nanostructure (metallic disk on top of a Bragg mirror). We show that the radiation pattern can be controlled by changing the excitation spot on the disk with only micrometer precision, in a manner which can be well described by numerical simulations. A simplified analytical model suggests that the propagation length of the in-plane confined optical modes is a key parameter for beaming control

High quality factor confined Tamm modes

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Tamm Cavity in the Terahertz Spectral Range

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Metasurface for Reciprocal Spin-Orbit Coupling of Light on Waveguiding Structures

International audienceLight manipulation through spin-orbit coupling opens new perspectives in photonics and particularly in integrated optics. The reverse spin Hall effect, where the guided wave direction affects the polarization properties of the light scattered by a nanostructure, is a key effect for the development of new functionalities at the connection between integrated structures and free space, and could find application in chiral quantum optics, modulation, and multiplexing. We show that metasurfaces represent a promising platform for the reverse spin Hall effect. Using a periodic array of Λ-shaped metallic nanoantenna, we control the polarization of the extracted light with the guided wave-propagation direction, but also the number of output directions and the polarization of each one. These results and the versatility of metasurfaces for the spin Hall effect could be extended to various frequencies and materials, such as silicon photonics at telecom wavelength

Surface plasmon generation through hybridization with Tamm modes

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