Low-Cost Micromechanically Tunable Optical Devices: Strained Resonator Engineering, Technological Implementation and Characterization

The rapid growth of the optical communication branches and the enormous demand for more bandwidth require novel networks such as dense wavelength division multiplexing (DWDM). These networks enable higher bitrate transmission using the existing optical fibers. Micromechanically tunable optical microcavity devices like VCSELs, Fabry-Pérot filters and photodetectors are core components of these novel DWDM systems. Several air-gap based tunable devices were successfully implemented in the last years. Even though these concepts are very promising, two main disadvantages are still remaining. On the one hand, the high fabrication and integration cost and on the other hand the undesired adverse buckling of the suspended membranes. This thesis addresses these two problems and consists of two main parts: • PECVD dielectric material investigation and stress control resulting in membranes shape engineering. • Implementation and characterization of novel tunable optical devices with tailored shapes of the suspended membranes. For this purposes, low-cost PECVD technology is investigated and developed in detail. The macro- and microstress of silicon nitride and silicon dioxide are controlled over a wide range. Furthermore, the effect of stress on the optical and mechanical properties of the suspended membranes and on the microcavities is evaluated. Various membrane shapes (concave, convex and planar) with several radii of curvature are fabricated. Using this resonator shape engineering, microcavity devices such as non tunable and tunable Fabry-Pérot filters, VCSELs and PIN photodetectors are succesfully implemented. The fabricated Fabry-Pérot filters cover a spectral range of over 200nm and show resonance linewidths down to 1.5nm. By varying the stress distribution across the vertical direction within a DBR, the shape and the radius of curvature of the top membrane are explicitely tailored. By adjusting the incoming light beam waist to the curvature, the fundamental resonant mode is supported and the higher order ones are suppressed. For instance, a tunable VCSEL with 26 nm tuning range, 400µW maximal output power, 47nm free spectral range and over 57dB side mode suppresion ratio (SMSR) is demonstrated. Other technologies, such as introducing light emitting organic materials in microcavities are also investigated.

Synthesis and characterisation of novel nitrogen and fluorine containing spirobifluorene derivatives for electronic applications and crystal engineering

Among organic materials, spirobifluorene derivatives represent a very attractive class of materials for electronic devices. These compounds have high melting points, glass transitions temperatures and morphological stability, which makes these materials suitable for organic electronic applications. In addition, some of spirobifluorenes can form porous supramolecular associations with significant volumes available for the inclusion of guests. These molecular associations based on the spirobifluorenes are noteworthy because they are purely molecular analogues of zeolites and other microporous solids, with potential applications in separation, catalysis, sensing and other areas.

Experience in introduction of English terminology in engineering lessons: methodology and evaluation

This communication explains a experience for the introduction of English terminology in a technical degree of higher education. We present the methodology and assessment procedures used to evaluate the way the students perceived the introduction of terminology in English in two different subjects from 3rd and 5th year courses of a Computer Science degree in which English was not the vehicular language. We propose a strategy based on two main pillars, namely: 1) The design of materials, explanations, and exams, paying particular attention to the way in which the specific terminology was exposed to the students, and 2) The assessment of the impact in the students by means of the analysis of the feedback trough a set of enquiries. Our experience showed that the students responded very positively to the introduction of English terminology, and presented an affirmative feedback about the impact that an improvement of their linguistic abilities would have in their future work. Further, we present statistics regarding the use of English as the vehicular language for technical reports, which is envisaged as very useful by the students. Finally, we propose a set of questions for further debate which are centered in the role that English terminology should pay in technical degrees, and about the way in which universities should deploy resources in English languages within the different Syllabus

Hybrid Brains - Biology, Technology Merger

In this paper an attempt has been made to take a look at how the use of implant and electrode technology can now be employed to create biological brains for robots, to enable human enhancement and to diminish the effects of certain neural illnesses. In all cases the end result is to increase the range of abilities of the recipients. An indication is given of a number of areas in which such technology has already had a profound effect, a key element being the need for a clear interface linking the human brain directly with a computer. An overview of some of the latest developments in the field of Brain to Computer Interfacing is also given in order to assess advantages and disadvantages. The emphasis is clearly placed on practical studies that have been and are being undertaken and reported on, as opposed to those speculated, simulated or proposed as future projects. Related areas are discussed briefly only in the context of their contribution to the studies being undertaken. The area of focus is notably the use of invasive implant technology, where a connection is made directly with the cerebral cortex and/or nervous system. Tests and experimentation which do not involve human subjects are invariably carried out a priori to indicate the eventual possibilities before human subjects are themselves involved. Some of the more pertinent animal studies from this area are discussed including our own involving neural growth. The paper goes on to describe human experimentation, in which neural implants have linked the human nervous system bi-directionally with technology and the internet. A view is taken as to the prospects for the future for this implantable computing in terms of both therapy and enhancement.

NUCEL (Cell and Molecular Therapy Center): A multidisciplinary center for translational research in Brazil

Social and economical development is closely associated with technological innovation and a well-developed biotechnological industry. In the last few years, Brazil`s scientific production has been steadily increasing; however, the number of patents is lagging behind, with technological and translational research requiring governmental incentive and reinforcement. The Cell and Molecular Therapy Center (NUCEL) was created to develop activities in the translational research field, addressing concrete problems found in biomedical and veterinary areas and actively searching for solutions by employing a genetic engineering approach to generate cell lines over-expressing recombinant proteins to be transferred to local biotech companies, aiming at furthering the development of a national competence for local production of biopharmaceuticals of widespread use and of life-saving importance. To this end, mammalian cell engineering technologies were used to generate cell lines over-expressing several different recombinant proteins of biomedical and biotechnological interest, namely, recombinant human Amylin/IAPP for diabetes treatment, human FVIII and FIX clotting factors for hemophilia, human and bovine FSH for fertility and reproduction, and human bone repair proteins (BMPs). Expression of some of these proteins is also being sought with the baculovirus/insect cell system (BEVS) which, in many cases, is able to deliver high-yield production of recombinant proteins with biological activity comparable to that of mammalian systems, but in a much more cost-effective manner. Transfer of some of these recombinant products to local Biotech companies has been pursued by taking advantage of the Sao Paulo State Foundation (FAPESP) and Federal Government (FINEP, CNPq) incentives for joint Research Development and Innovation partnership projects.

Materials Collection Creation and Administration: A New Role for Libraries (White Paper)

The Problem/Opportunity: To define, identify, and guide design-based materials collections in academic settings and foster community among those with existing collections and/or those considering creating and supporting one. Contents and topics: What is a materials collection? Why have a materials collection? Acquisition strategies Organizational approaches Programming possibilities Symposium summary Resources

Materials Education and Research in Art and Design: A New Role for Libraries - Session 3. RISD Faculty

Faculty from Rhode Island School of Design representing Interior Architecture, Industrial Design, and Textiles detail their thoughtful interactions with materials.

Materials Education and Research in Art and Design: A New Role for Libraries - Session 4. Designers

Designers respond to issues and synthesize ideas from throughout the day as voices from the field who directly encounter the need for recently graduated students to possess the ability to investigate and interrogate materials.

Materials Education and Research in Art and Design: A New Role for Libraries - Session 2. Educators

Educators representing interactions with materials speak to critical approaches, life-cycle concerns, critical thinking of composition/process/properties.