Optical Characterization of the Samples: Absorption spectra were recorded in the 200±900 nm range using a Lambda 9000 Perkin-Elmer spectrophotometer. The samples were diluted by a factor of around 100 in DEG; the dilution factors slightly differed for the different samples in order to ensure analysis of solutions with the same concentrations of oxide particles (0.028 mg mL ±1 ). This allows comparison of samples with the same oxide concentration diluted in the same solvent.The UV excitation and emission spectra were measured at room temperature with a broad excitation at 325 nm. The excitation source was a 450 W xenon lamp coupled to an Hitachi Jobin±Yvon monochromator with a 300 groves mm ±1 grating. The detected emission was transferred by an optical fiber, placed at 45 to the sample, and recorded by an air-cooled charge-coupled device camera. All the samples with the same size oxide particles (either oxide colloids, gold/oxide nanocomposites, or gold/oxide mixtures) have been diluted in DEG before characterization to obtain the same concentration of Tb 3+ -doped Gd 2 O 3 in mass of oxide per mL. For the solutions containing oxide particles with a diameter of 3 nm, the concentration of oxide was 2.8 mg mL ±1 , and for those containing particles with a diameter of 8 nm, the concentration of oxide was 18.9 mg mL ±1 . Finally, the emission spectra were systematically corrected from the white luminescence due to the emission of the DEG and the quartz container.

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In this paper, we present the integration of an absorbing photonic crystal within a monocrystalline silicon thin film photovoltaic stack fabricated without epitaxy. Finite difference time domain optical simulations are performed in order to design one- and two-dimensional photonic crystals to assist crystalline silicon solar cells. The simulations show that the 1D and 2D patterned solar cell stacks would have an increased integrated absorption in the crystalline silicon layer would increase of respectively 38% and 50%, when compared to a similar but unpatterned stack, in the whole wavelength range between 300 nm and 1100 nm. In order to fabricate such patterned stacks, we developed an effective set of processes based on laser holographic lithography, reactive ion etching and inductively coupled plasma etching. Optical measurements performed on the patterned stacks highlight the significant absorption increase achieved in the whole wavelength range of interest, as expected by simulation. Moreover, we show that with this design, the angle of incidence has almost no influence on the absorption for angles as high as around 60°.

We propose and demonstrate a hybrid photonic-plasmonic nanolaser that combines the light harvesting features of a dielectric photonic crystal cavity with the extraordinary confining properties of an optical nano-antenna. For this purpose, we developed a novel fabrication method based on multi-step electron-beam lithography. We show that it enables the robust and reproducible production of hybrid structures, using a fully top-down approach to accurately position the antenna. Coherent coupling of the photonic and plasmonic modes is highlighted and opens up a broad range of new hybrid nanophotonic devices.

The control of surface wetting properties to produce robust and strong hydrophobic and oleophobic effects on intrinsically oleophilic surfaces is at the heart of many technological applications. In this paper, we explore the conditions to observe such effects when the roughness of the substrate is of fractal nature and consists of nanofeatures obtained by the ion track etching technique. The wetting properties were investigated using eight different liquids with surface tensions gamma varying from 18 to 72 mN m(-1). While it is observed that all the tested oils readily wet the flat substrates, it is found that the contact angles are systematically exalted on the rough surfaces even for the liquids with very low surface tension. For liquids with gamma > or = 25 mN m(-1) an oleophobic behavior is clearly induced by the nanostructuration. For liquids with gamma < 25 mN m(-1), although the contact angle is enhanced on the nanorough surfaces, it conserves its oleophilic character (theta* lower than 90 degrees). Moreover, our experiments show that even in the case of hexane, liquid having the lowest surface tension, the homogeneous wetting (Wenzel state) is never reached. This high resistance to liquid impregnation is discussed within the framework of recent approaches explaining the wetting properties of superoleophobic surfaces.