PHENOmenon organized a Focus Seminar on Optically Engineered Surfaces and their manufacturing, as a parallel activity within the SMS 2019 conference in Lisbon.
Pablo M. Romero (AIMEN, Spain) presents the session, introducing the PHENOmenon project, its challenges and proposed solutions to produce 3D optical nanostructures with high resolution and extremely reduced fabrication time, through massive parallelization and advanced photochemistry.
First Session - Frontiers of Multiphoton Lithography
Keynote speech: Prof. Maria Farsari (IESL- FORTH, Greece)
Prof. Farsari delivered a very interesting talk on the fabrication of 3D structures with sub-100 nm resolution through Direct Laser Writing (DLW). The fabrication of different structures with various materials was presented and discussed, with special emphasis on those structures/materials for biomedical applications. Moreover, the re-use of biological materials as support for DLW fabrication and the fabrication of auxetic structures with highly potential application in biomedical devices such as coronary or pulmonary stents were some of the topics covered in the keynote speech. With this talk, Prof. Farsari summarized not only her most remarkable experimental results but also her point of view on the technique, pointing out that, while the low throughput of the technique is expected to be solved parallelization is expected overcome soon by parallelization, there is a strong need to develop more efficient materials, oriented to the application of interest.
Professor Kevin Heggarty (IMT-A, France)
Prof. Heggarty presented his most recent results on the massive parallelization of the 2 photon polymerization (2PP) technique, by using Diffractive Optical Elements (DOEs) and amplitude or phase-modulated Spatial Light Modulators (SLMs), carried out in the frame of the PHENOmenon project. An overview of the most relevant challenges that arise from massive parallelization of 2PP from an optical/chemical point of view were presented, with special attention to the proximity effects that appear as a consequence of the short distance used between parallel beams.
Prof. Patrice Baldeck (ENS Lyon, France)
Prof. Baldeck introduced his latest theoretical and experimental results on the fabrication of sub-wavelength diffractive elements with high aspect ratio for surface optics. In his talk, the design of micron-sized polymeric diffraction lenses and their possible fabrication routes through parallel 2PP were discussed.
Second Session - Advanced optical functional structures
Keynote speech: Dr. Lieven Pennik (PlanOpSim, Belgium)
Dr. Pennik introduced the state of the art regarding the simulation of optical metasurfaces and their influence on their development for near future applications. A review of the challenges that must be faced during the simulation of metasurfaces, taking into account their particular expected optical properties, was presented and discussed. The extremely demanding needs in terms of computation workload for this simulation was introduced, presenting several alternatives that could provide accurate results with a reduced computational time.
Prof. José Miguel López-Higuera (University of Cantabria, Spain)
Prof. López-Higuera presented a review of the most interesting results that his research group has found on the fabrication of tiny fibre sensors through laser assisted techniques. In this way, the production of different optical interferometers inside optical fibres through femtosecond laser direct writing was introduced, explaining their application for the fabrication of fibre sensors or transducers that could be used for example in gas sensing.
Dr. Francisco Gontad (AIMEN Technology Centre, Spain)
Dr. Gontad introduced a new approach for the fabrication of high quality optical grade microstructures through injection moulding, where the optical microstructures also serve as the optoelectronic device encapsulation. The European project, FLOIM, where this new fabrication route will be developed, was presented, pointing out the synergies that could be created with the PHENOmenon project, in terms of microstructure design and fabrication technology. In this way the parallel 2PP technology developed in PHENOmeno could provide a very promising mould fabrication route with great advantages in terms of resolution and fabrication speed.
Dr. Salvador Eslava (University of Bath, UK)
Dr. Eslava introduced the preparation of photoelectrodes for solar fuels. In particular, the preparation of inexpensive photoanodes based on nanostructured TiO2, α-FeO2 or more innovative CsPbBr3 perovskites was discussed. Their electrical characterization was also discussed with special attention to the fabrication of the perovskite photoanodes with an inexpensive carbon protective layer, which provides more than 30 h of continuous work immersed in water with a Faradaic efficiency of 82% and achieving photocurrents above 2 mA cm−2 at 1.23 VRHE.