High sensitivity zinc oxide (ZnO) tetrapods (TPs) have been functionalized by nucleating cadmium sulphide (CdS) nanoparticles (NPs) directly on their surface with a spotted coverage thanks to an optimized synthesis in dimethylformamide (DMF). The obtained hybrid coupled material has been used to realize a gas sensing device with a highly porous nanostructured network, in which the proper alternation of ZnO-TPs and CdS-NPs gives rise to unconventional chemoresistive behaviours. Among the different tested gases and vapours, the sensor showed a unique fingerprint response-inversion between 300 °C and 400 °C only for nitrogen dioxide (NO2) and acetic acid (CH3COOH).

Optical writing and subsequent optical reading of sub-micron size features has been obtained at room temperature on a spin-coated film of polymethecrylate added with azobenzene mesogenic side groups (PMA4), by means of scanning near-field optical microscopy (SNOM). Illumination with blue or LW light through the SNOM aperture induces conformational transitions in the side units, obtaining their orientation in a localized region. Optical writing and topographic reading with subwavelength resolution have been demonstrated. The pure optical readback is obtained by laser light at 690 nm through the aperture, in the polarization-modulation mode that provides sensitivity to dichroism and birefringence. Equally spaced lines have been written and subsequently imaged, presenting about one micron width in the birefringence image and about 600 nm width in the scattering optical image. Local erasure of optical information can be obtained by using green light at 543nm with modulated polarization through the SNOM tip, in order to destroy the molecular alignment

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We have applied pulsed laser deposition (PLD) to fabricate YBCO/YSZ films (short length) onto biaxially textured NiFe substrates. Macroscopic characterization of the samples has been carried out by electrical measurements, XRD patterns and pole figures. Our best films are characterized by T cs around 89 K and transition widths around 5–6 K. Bragg–Brentano spectra and pole figures acquired on the {111} peak for YSZ and {013} for YBCO show the achievement of the correct crystalline structure and stoichiometry both in YSZ and in YBCO layers. They are largely in-plane textured (respectively (001) <110> for YSZ and (001) <100> for YBCO), and the superconducting YBCO layer exhibits a relatively low mosaicity. Atomic-force microscopy (AFM) analysis confirmed the presence of large grains (1–2 μm typical dimensions), and the occurrence of a complex morphology in the YBCO layer.