Nanostructuring Optical Waveguides by Focused Ion Beam Milling. Near-Field Characterization.

Available online at http://www.kps.or.kr/home/kor/journal/library/search.asp?International audienceNanostructures have become an attractive subject due to many applications, particularly the photonic bandgap effect observed in photonic crystals. Nevertheless, the fabrication of such structures remains a challenge because of accurate requirement concerning regularity, shape, hole depth etc. of the structure. E-beam lithography permits a good control of dimensional parameters but needs a 1-step fabrication process. In our work, we have to combine traditional strip-load waveguides (SiO2/SiON/SiO2 on Si) and nanostructures whose dimension are totally different. This imposes a 2-step process where waveguides and nanostructures are successively fabricated. We have at our disposal different ways to characterize these nanostructures. A direct aspect control during and after FIB treatment can be achieved by FIB and SEM imaging. Scanning near-field optical microscopy (SNOM) is currently the most effective way to test guiding confinement in such surface structures by detecting the evanescent field

Nanostructuring lithium niobate substrates by focused ion beam milling

We report on two novel ways for patterning Lithium Niobate (LN) at submicronic scale by means of focused ion beam (FIB) bombardment. The first method consists of direct FIB milling on LiNbO3 and the second one is a combination of FIB milling on a deposited metallic layer and subsequent RIE (Reactive Ion Etching) etching. FIB images show in both cases homogeneous structures with well reproduced periodicity. These methods open the way to the fabrication of photonic crystals on LiNbO3 substrates

Electrodynamics in complex systems: Application to near-field probing of optical microresonators

This paper discusses recent theoretical efforts to develop a general and flexible method for the calculation of the field distributions around and inside complex optical systems involving both dielectric and metallic materials. Starting from the usual light-matter coupling Hamiltonian, we derive a self-consistent equation for the optical field in arbitrary optical systems composed of N different subdomains. We show that an appropriate solving procedure based on the real-space discretization of each subdomain raises the present approach to the rank of an accurate predictive numerical scheme. In order to illustrate its applicability, we use this formalism to address challenging problems related to nonradiative energy transfers in near-field optics. In particular, we investigate in detail the detuning of a microresonator probed by a near-field optical probe.</p

Microscopie optique de l'imagerie à la physique à l'échelle nanométrique

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De la microscopie à la nanoscopie optique

Cours n°2International audienceCours sur les développements récents de la microscopie optique (profilométrie interférentielle, contraste de phase, super-résolution, éclairage structuré, STED, 4-PI, microscopie holographique numérique, champ proche ...

Microscopies et caractérisation des surfaces

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Les microscopies et la caractérisation des surfaces

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