ETOPIM7 Concluding Session ...
Future Directions for Composite Science Research
- Formation of the ETOPIM Association: the ETOPIM Conference has been run six times since the inaugural conference in Columbus, Ohio in 1977. Each successive organizing committee has had to be independent of its predecessor, and at times had had less than perfect preservation of important information with regard to invitation lists for delegates, financial support and contacts, etc. The proposal was put and adopted by those attending to form an ETOPIM Association, to provide continuity between ETOPIM Conferences. The Association would function with the minimum of bureaucracy, but would preserve the database of contacts from ETOPIM7, and provide support to funding initiatives for ETOPIM8, etc.
- Presentation of Awards: the University of Sydney sponsored three prizes for presentations by students working in Australia. These were awarded to Elizabeth Kyriakou, Shannon Orbons and Michelle Rigozzi, and were presented by the University’s Dean of Graduate Studies, Prof. Masud Behnia. Also, ETOPIM7 sponsored a prize for the best presentation from a student sponsored by NSF. This was presented by Prof. Graeme Milton to Zubin Jacob.
- Future Directions for Research in Composite Science: this topic was addressed by a panel composed of Prof Sir John Pendry, Dr. Stuart Anderson, and Prof Ken Golden, and was chaired by Prof Ross McPhedran. Reactions and additions from the floor are added at the end of each speaker’s comments.
- Prof Sir John Pendry: plasmonics and metamaterials. Metamaterials constituted a major theme at ETOPIM7. For ETOPIM8, it would be good to see the issues of material losses thoroughly addressed. Another aspect requiring progress is that of manufacturing metamaterial systems. A theoretical question requiring solution is that of homogenization of metamaterials. Another aspect requiring attention is the use of metamaterials for controlling magnetic fields. With regard to plasmonics, an issue for the field is the over-reliance on silver as the material of choice, given that its optical losses are too high. There should be a through exploration of alloy systems, a strategy which proved so successful in improved semiconductor properties and may well deliver materials supporting plasmons with increased lifetimes. Another issue of importance for plasmonics is the control of surface flatness. With regard to superresolution, two different techniques had been described at ETOPIM7 for delivering this in the far-field, one by Zubin Jacob, and the other by Mathias Fink. Current progress in this area was exciting. A comment from the floor was that an extra dimension in metamaterials was their use in temporal profiling of signals.
- Dr. Stuart Anderson: composite materials in defence science. Dr. Anderson presented personal views, in no way representing those of his employer, the Defence Science and Technology Organisation.
- The key defence role of the new materials for the near future will lie in miniaturization of existing operational capabilities, rather than implementation of new concepts, due to long time constants for serious innovations in defence.
- Composite science will play a central role in the development of more compact sensors, lighter and stronger airframes and so on, especially for unmanned aerial vehicles. Metamaterial lenses for radar are one promising development, as are so-called ‘smart skins’ and the extension of coherent electromagnetics to terahertz frequencies.
- Stealth technologies will continue to be of interest, but most of the more speculative concepts will not find their way into operational systems for a long time, if ever. There are several reasons for this of which perhaps the most significant is that nearly all the proposed cloaking and ‘invisibility’ techniques are very narrow band, or apply on a limited range of incident angles, whereas radars and other sensors are trending towards ever wider bandwidths and bistatic or multistatic scattering geometries.
- Target detection exploiting environmental impact is a promising indirect method. Metamaterials coupled with superconductors may enable deployable physical devices responding to unusual electromagnetic signatures.
- There is a truism that even now we can detect almost anything, but we can classify almost nothing. This leads to a need for technologies able to recognize friend from foe in challenging environments. There will be opportunities for advanced materials in the design of reliable signature and authentication systems which are hard to deceive.
- A second truism is that, if you are radiating, you can be sure someone’s listening. This leads to a requirement for novel methods of control of signal paths. Time reversal techniques and their variants are active areas of defence research.
- Prof Ken Golden: composites in environmental science: The ETOPIM Conferences provide a unique resource, in the perspectives, range of expertise and inter-community linkages they enable. This is important in environmental science, in which composite structures figure widely (e.g., geophysical resources, glaciers, floating ice and other structures important in climate change monitoring, pollutant monitoring, remote sensing). A valuable technique is the use of electromagnetic radiation, but this generally entails a complex inversion problem which may require sophisticated analysis. Given our inadequate knowledge of many important environmental parameters, composite material science will be important in reducing their error bars. Such environmental science problems will require teams of people who can share skills across subject boundaries, and bring techniques together to supply an osmosis of ideas which will be required to solve these globally-important questions.
- General comments from the floor: Prof. David Bergman noted that the study of acoustic properties of composites was an area which could benefit more from the expertise of the ETOPIM community. Prof. Ping Sheng noted that the ETOPIM Conferences have played and continue to play a key role. In an era of many conferences, ETOPIM was still unique, in that it evolved to cover emerging areas, but retained its diversity, interdisciplinarity, and linkages between scientific, mathematical and engineering viewpoints. Prof. Richard Blaikie noted the value of microstructural analysis and surface science techniques to composite science. Prof. Graeme Milton noted that an important emerging area of composite science was in fuel cell technology, where fundamental challenges remained. Prof. Geoff Smith spoke of the challenge of providing multi-functionality in a single structure. One deceptively prosaic example was in design of windows, where optical functionality was obvious, but needed to be combined with environmental properties. There were many other examples where good performance with respective to many parameters was required, and composite systems had the potential to provide global optimality, rather than narrow, single-parameter optimality.
Minutes compiled by Ross McPhedran; notes taken by Drs. Julie Cairney and Boris Kuhlmey.
Sydney, August 2006