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4 Conclusions and Recommendations The field of new materials research and crystal growth is in the midst of sweep- ing institutional and geographical change. Historically, central research laboratories of large U.S. corporations led the nation and the world in the work of discovering and synthesizing new crystals. In these facilities the vast majority of crystal growth techniques were developed and there, also, important postgraduate training was provided to successive generations of crystal growers. In the past few decades, s Â everal factors have caused these industrial capabilities in the United States to shrink to the point of near disappearance. This loss has become even more criti- cal with the decrease in federal funding in support of the discovery and growth of crystalline materials (DGCM), as discussed in Chapter 3 of this report. This deterioration in capacity occurred despite continued high demand for such materials and the value associated with their development. U.S. Âresearchers could readily use more crystalline samples; as discussed earlier, U.S. scientists and technologists are frequently at a competitive disadvantage because of inadeÂ quate access to new crystalline materials and large, high-quality single crystals. As described in the discussion on gallium arsenide (GaAs) in Chapter 1 (see the section entitled âExample in the Area of Thin Films: Gallium Arsenide-Based Heterostructuresâ), ultrahigh-purity crystals exhibiting very high charge carrier mobility are qualitatively different from materials with low or moderate carrier mobility. Such high-purity crystals continue to lead to the discovery of new fun- damental physical phenomena, not just in GaAs but in systems that produce novel states of condensed matter. Further, U.S. federal agencies have made significant investments in major materials characterization and analysis capabilities, such as 126
Conclusions and R e c o m m e n dat i o n s 127 synchrotron x-ray sources, neutron-scattering facilities, electron microscopes, and high magnetic field facilities. The availability of these leading-edge facilities offers U.S. scientists the opportunity to discover new science and to optimize crystalline materials for future technological applications, provided they have access to single- crystal samples of newly discovered material and large, high-quality single crystals for neutron scattering. Discovery of new crystalline materials and growth of single crystals have been shown continually to be highly leveraged activities, yielding disproportion- ately large returns on investment while helping to address important national issues related to energy, information, transportation, national security, health, and other areas. As discussed in Chapter 1 (see the section entitled âExample of High-ÂTemperature Superconductivityâ), this leveraging recently was seen in the explosion of research following the discovery of high-transition temperature (Tc) superconductivity, which led to new metrologies and analysis capabilities that pro- duce new fundamental science as well as to new modes for efficiently transporting energy. Similarly, this leveraging is illustrated historically by the growth of entire industries in the computer field, which were able to arise only after the DGCM community developed the capability to produce high-purity crystalline silicon and III-V compound semiconductors. Todayâs scientists and engineers in the United States are severely constrained by a research environment in which crystal supply is limited at a time when governÂ ments in selected countries in Asia and Europe have recognized the foundational importance of new materials and high-purity single crystals, and in some cases will not make them available for political reasons. In contrast to the current state of affairs in the United States, these countries are becoming much stronger in the discovery of important new materials and phenomena through strategic invest- ments. It must be emphasized that if these trends continue, U.S. scientists, engi- neers, and industrial facilities either will become increasingly dependent on materials d Â eveloped and grown outside the United States or will not have access to needed materials at all. Comprehensive Solution to Enhance Competitiveness In this chapter, the Committee for an Assessment of and Outlook for New Materials Synthesis and Crystal Growth recommends ways to address the issues and opportunities identified in this report. Concerted efforts will be required from those engaged in DGCM research, from the educational and research institutions in which those efforts take place, and from those agencies that provide funds and other sup- port for scientific research. Specifically, the committee believes that a comprehensive solution to providing future opportunities in the discovery and growth of crystalline materials in the United States should include the following elements:
128 Frontiers in C rys ta l l i n e M at t e r â¢ A focused, multiagency initiative for establishing and sustaining programs specifically directed toward driving the discovery and growth of new crys- talline materials; â¢ Shared, large-scale facilities and small-scale equipment for growth of new materials, large crystals of existing materials, and thin-film systems, and for advancing the state of the art of crystal growth; â¢ Increased capability for hands-on training in discovery and growth of crystal- line materials for both new and established researchers; â¢ Crystalline material synthesis performed in multidisciplinary research envi- ronments complete with infrastructure and operational support (operations and technicians); â¢ A crystal growth network for the distribution of samples and information to amplify the impact of research support by helping to build new collaborations among the crystal growth, measurement, and theory communities; and â¢ Technology transfer to help address the needs of industry in areas of crystal growth methods and prototype crystalline material development, including codevelopment of technology. Increasing Agency Engagement in Advancing the Discovery of New Crystalline Materials and New Methods of Crystal Growth A significant gap has developed in this country between the demand for and the supply of both new crystalline materials and large, high-quality single crystals. The large industrial research laboratories that historically led the nation in dis- covering those new crystalline materials and in developing techniques for growing pure crystals no longer engage in these activities to a significant degree. Neverthe- less, the need for basic research in materials for future technologies, especially for energy, information, and security, is greater than ever, thus imparting urgency to the remedial measures suggested in this report. The natural entities to bridge this gap are those agencies already involved in funding basic and applied research. However, in part because of how the field of DGCM has historically developed and in part because of the inherently multiÂ disciplinary nature of the field, the full breadth of DGCM research needs do not fit existing programs within any single funding agency. Further, because the DGCM field impacts a broad set of technologies encompassing energy, information, secu- rity, and industrial standards, the committee believes that a multiagency approach among relevant agencies should be undertaken to help bridge this gap. Therefore, the Committee for an Assessment of and Outlook for New Materials Synthesis and Crystal Growth makes the following recommendation:
Conclusions and R e c o m m e n dat i o n s 129 Recommendation 1. Develop a focused, multiagency initiative to strengthen U.S. efforts to discover and grow new crystalline materials. Agencies that fund research involving discovery science, energy, information, and security that requires crystalline materials in some respect, such as the Depart- ment of Energy (DOE), the National Science Foundation (NSF), the Department of Commerce (DOC), and the Department of Defense (DOD), should develop a coordinated initiative designed to strengthen DGCM activities and to provide for their long-term, sustainable support. The broad goals of such an initiative should be to establish crosscutting synthesis capabilities, educational instruments, and openly available cyber resources that will enable broad research efforts. The recommended initiative would consist of new programs focusing on the discovery and synthesis of new crystalline materials with novel properties, while placing high importance on establishing linkages between fundamental research and technology development, with the strong and ongoing participa- tion of industry. Programs funded through such an initiative should provide the range of support necessary to address the spectrum of research needs of this field, from support for small-scale crystal growth laboratories run by single investiga- tors to large-scale centralized facilities for crystalline materials discovery and the growth and characterization of single crystals (addressed in Recommendation 2). The costs of such programs will also vary, depending on their scope and scale. For comparison, the committee notes that in the discussion in Chapter 3, in the section entitled âInternational Activities,â it sets out the present costs for funding individuals and small groups of investigators in the Core Research for Evolutional Science and Technology and Ministry of Education, Sports, Science and Culture programs currently supported in Japan. The precise forms of programs to be funded should be designed by the agencies and should be subject to competitive review. A number of individual investigators currently funded by DOE and NSF, in both national laboratories and universities, engage, as part of their overall research activities, in new materials discovery and single-crystal growth. These investigators provide a base of expertise on which to develop the detailed approaches needed to meet such an initiativeâs goals for a com- petitive review process. It also makes sense to solicit guidance from present DGCM researchers on the structure of a future funding model for DGCM research and on the means of implementing the model. Finally, the proposal development process itself would generate visions for effectively realizing materials-driven science of the future, with the funding agencies choosing ways to implement the vision. The process of competitive review should call for proposals to implement expanded new research activities in materials discovery and crystal growth and for proposals offering a range of educational initiatives, from workshops to on- site training to placement of agency-funded interns. The infrastructure to be
130 Frontiers in C rys ta l l i n e M at t e r funded through this review process should include support for the availability of technicians and specialists for crystallographic characterization and innovative growth techniques. The committee urges DOE and NSF, the principal agencies that now fund the majority of such research, to establish as soon as is practicable a committee to evaluate the merits of this recommendation and a procedure for implementing it. The committee urges other agencies with programmatic interests in strengthened DGCM efforts, especially DOC and DOD, to participate actively in the initiative. Advancing the State of the Art in the Discovery and Growth of Crystalline Materials In previous decades, one important attribute of large central research laborato- ries in companies such as Bell Laboratories, IBM, General Electric, Westinghouse, and RCA was the presence of large, interdisciplinary teams whose members had the capability to address the âbig problemsâ with a critical mass of researchers and facilities. Such teams were able to characterize a sample and provide rapid feedback to the crystal growers about the sample composition, crystalline nature, and related information. The immediate involvement of theorists at these large DGCM centers also played a vital role in achieving an understanding of physical properties that gave key feedback to the growers. That feedback, in turn, guided the crystal growersâ efforts to improve the purity and crystalline quality of the desired material. These large central research laboratories not only developed and purified new crystalline materials, but they also trained the next generation of crystal growers and devel- oped most of the crystal growth and purification techniques in common use today, such as techniques for single-crystal growth, float zone refining for purification of crystals, molecular-beam epitaxy for growth of films with atomic-layer control, and so forth. Such an environment is essential for the cost-effective and timely synthesis of new materials; for the growth of large, high-quality crystals needed for research and technological applications; and for sustaining DGCM research and education. Therefore, the Committee for an Assessment of and Outlook for New Materials Synthesis and Crystal Growth makes the following recommendation: Recommendation 2. Develop discovery and growth of crystalline materials âcenters of expertise.â Funding should be provided for one or more centers that are capable of addressing the broadscale issues arising in the DGCM area. Centers have a role that cannot be filled by small programs. In contrast to small programs, centers can provide the needed infrastructure to house specialized facilities and the robust multidisciplinary environment needed for cutting-edge materials development.
Conclusions and R e c o m m e n dat i o n s 131 The purpose of these centers would be to address a range of problems including those requiring large-scale facilities, facilities for processing toxic chemicals, and facilities requiring significant technical support. In addition to one or more centers addressing broadscale DGCM issues, there should be one or more centers whose main mission is to address problems of crystal growth of immediate interest to U.S. industry. Working on a cost-recovery basis, these industry-oriented centers would be responsible for forming strong industrial partnerships, engaging in technology development with their industrial partners, and maintaining the expertise and infrastructure needed for industrial crystal growth. One or more of these large-scale centers might be focused on either a mateÂrials chemical class(es) or a materials synthesis technique(s). Several of these centers could be user facilities located at existing Federally Funded Research and Devel- opment Centers and would thus serve to enrich the user experience by offering access not only to synthesis facilities and expertise but also to existing advanced- measurement capabilities such as major x-ray and neutron facilities. Other centers could be on a smaller scale, residing at a university and formed around a particular expertise not requiring wide-ranging infrastructure support. In general, most if not all of these centers, whether large-scale, small-scale, or industry-oriented, should support a small number of education and training programs that explicitly address the discovery and growth of crystalline materials and complement the university- based research and education in DGCM addressed in Recommendation 3. While the costs of such centers will vary, depending upon the scope of their mission, the committee notes that in the discussion in Chapter 3, in the section entitled â Â International Activities,â it sets out the present costs for funding comparable programs in Europe. It is noted that the Physics Frontiers Centers program operated by NSF offers many of the funding and selection characteristics being considered by this comÂ mittee. The NSF program might thus provide a good model for developing a program to support centers of expertise for DGCM activities. Sustaining Expertise in the Discovery and Growth of Crystalline Materials As noted earlier in this report, industrial research laboratories not only devel- oped and purified new crystalline materials, they also trained future generations of crystal growers. While much of the expertise of those industrial laboratories has been retained in the migration of the industrial scientists to universities and national laboratories, the ability to train their successorsâthe new generation of materials developers and crystal synthesizersâhas not been maintained. A focused effort to replace these valuable education and training capabilities must be undertaken. Therefore, the Committee for an Assessment of and Outlook for New M Â aterials Synthesis and Crystal Growth makes the following recommendation:
132 Frontiers in C rys ta l l i n e M at t e r Recommendation 3. Develop and sustain programs specifically designed to strengthen and sustain education and training in the field of the discovery and growth of crystalline materials. Federal agencies should develop programs and policies that focus on provid- ing the specific and often unique education and training needed for those engaged in developing crystalline materials and synthesizing large crystals. Reflecting the wide variety of capabilities and skill sets required for crystalline matter discovery (and analysis) and crystal growth (and characterization), this field is inherently interdisciplinary. As a result, special attention must be given to developing federally funded programs that encourage academic facilities to prepare the cross-Âdisciplinary curricula and opportunities for educating the next generation of U.S. DGCM sci- entists. Further, the centers of expertise proposed in Recommendation 2 should be charged with the responsibility of developing and implementing education and training programs that explicitly address discovery and growth of crystalline materials procedures as well as provide hands-on training opportunities for those entering the field. Larger-scale facilities, with their broad complement of technical staff, are particularly well suited to this hands-on training mission. (See Appendix G, âEducational Role of the Discovery and Growth of Crystalline Materials Centers of Expertise,â for further information.) Changing the Culture The culture of U.S. science does not generally reward DGCM synthesis research as much as it rewards measurement science. This culture is promulgated in universi- ties, where such solid-state synthesis research groups are more the exception than the rule. Given the departmental or discipline-centric nature of U.S. universities, coupled with the low level of federal funding for DGCM synthesis research, a strong natural academic âhomeâ has not been established for this field in U.S. universities. However, new academic disciplines emerge as the needs of society change. It is time to address barriers caused by factors such as differences between the discipline-centric nature of U.S. universities and the inherent interdisciplinary nature of DGCM research and limited funding for the acquisition and operation of equipment. While recogniz- ing the sentiment derived from industry that âculture eats strategy for breakfast,â it remains incumbent on U.S. funding agencies to work with universities to ensure that DGCM activities, both the education/training treated in Recommendation 3 and the research treated in Recommendations 1 and 2, have a long-term academic home. ââHeadline on a Wall Street Journal article, January 23, 2006; the origin of the headline was reported to be a sign in Ford Motor Companyâs war room, reminding company planners of the limitations of developing strategies.
Conclusions and R e c o m m e n dat i o n s 133 Therefore, the Committee for an Assessment of and Outlook for New Â Materials S Â ynthesis and Crystal Growth makes the following recommendation: Recommendation 4. Promote cultural changes to develop and solidify aca- demic programs in the field of the discovery and growth of crystalline materials. In order for the United States to have a strong and sustainable capability in the discovery and growth of crystalline materials, federal agencies should develop programs and policies that make it attractive for universities in the United States to hire crystal growers and promote robust research programs in this area by providing ample funding specifically for such work. The committee specifically urges that more crystal growers be hired into tenure-track positions at universi- ties. Because of the multidisciplinary nature of this type of work, the department that would be most appropriate for such programs would vary, depending on the university. However, because materials science departments provide robust support for research that straddles physics, chemistry, and diverse engineering disciplines, they would be a potential academic home. The committee also notes that some progress has been made in academia in leveraging multidisciplinary activities in the broad area of nanoscience, where centers and research institutes bring together researchers from diverse fields such as biology, physics, chemistry, and engineer- ing. Such efforts could provide a useful model for future success in the equally important area of DGCM. Improving Interaction and Cooperation Within the Discovery and Growth of Crystalline Materials Community The committee strongly believes that new approaches to communication are needed to advance the field of discovery and growth of crystalline materials. Spe- cifically, the committee recognizes that the internal communication processes that defined fruitful directions for DGCM activities in industrial laboratories greatly aided the development of materials. Such processes provided rapid response to synthesis needs as well as rapid feedback from measurement to synthesis. Fed- eral agencies should use a similar approach to promote communication among researchers through programmatic means. Obtaining the maximum benefit from the synthesis of crystalline materials requires the creation and support of a formally networked community that includes scientists and engineers who perform research on discovery and growth of crystalline materials, whether in large, shared facilities or as single investigators. These scientists need to interact strongly with one another and with scientists and engineers who perform research and develop technology based on these materials. Such communities developed naturally in large industrial
134 Frontiers in C rys ta l l i n e M at t e r research laboratories. While many of the scientists who engaged in DGCM activi- ties in industrial research laboratories have migrated to universities and national laboratories and continue to be extremely productive, there has been a significant loss in the close collaboration with other members of the networked community that existed in industrial laboratories. U.S. industry cannot afford to rebuild these capabilities in todayâs highly competitive, high-technology global environment; thus a different approach is required to address national needs in this area. The committee also notes that while this emphasis on collaboration requires significant transparency in certain aspects of research collaborations, fundamental aspects of intellectual ownership, which help to drive great discoveries, must be maintained. Greater transparency will require more formality and discipline among members of the DGCM community, including not only the scientists and engineers who grow the materials but also those who characterize the materials and those who rely on new materials and high-quality, high-purity single crystals for their scientific research. Such issues governing intellectual ownership in DGCM activities are not unlike those governing the research activities in national user facilities. To address these issues, the Committee for an Assessment of and Outlook for New Materials Synthesis and Crystal Growth makes the following recommendation: Recommendation 5. Develop a network approach for research-enhancing collaborative efforts in the discovery and growth of crystalline materials while preserving intellectual ownership. The committee believes that the enterprise of new crystalline materials dis- covery would greatly benefit from the creation of a network that has as its pri- mary missions both the communication of information related to synthesis and measurement capability across the United States and the coordination of DGCM programmatic activities. As a novel approach to scientific collaboration, the com- mittee envisions a âcrystalline materials networkâ that would both fulfill conven- tional needs for greater collaboration and enable the new modes of collaboration afforded by cyber infrastructure. The envisioned crystalline materials network would provide a virtual forum for organizing synthesis and measurement activities. Crystal growers would be able to announce the availability of new compounds on a DGCM Web site. Conversely, measurers would be able to request collaboration with a crystal grower to meet a specific sample need. The crystalline materials network would provide information access to the physical archive of already-synthesized samples stored in individual laboratories throughout the country, further enabling collaborations. This network would also maintain a database constructed for the specific needs of researchers to facilitate information searches on physical property categories that change with time as a result of the discovery of new properties of materials. The crystalline
Conclusions and R e c o m m e n dat i o n s 135 materials network would stimulate and promote research in promising new areas by enhancing the ability of growers to work with the appropriate researchers per- forming characterization measurements and by promoting the effective dissemi- nation of results. Outreach for the crystalline materials network, which would be critical, would be achieved through the organizing of professional meetings such as workshops, conferences, and summer schools devoted to the rapid development of DGCM science. While a crystalline materials network is a new concept, every effort should be made to capitalize on the self-formed networks that are characteristic of single- investigator science. The proposed network would preserve all the strengths of extant U.S. DGCM activities while providing guidance for the use of greater fund- ing resources to meet measurement demands (see Recommendation 1). A key benefit of a crystalline materials network would be greater access to samples for scientists who work neither at DGCM centers nor at institutions with crystal growth efforts (see Recommendation 2). The committee envisions that this network would be administered from a center of expertise with sufficient size and depth of scientific expertise to address day-to-day oversight requirements. Finally, to preserve intellectual property integrity, a common set of rules governÂ ing sample use would be needed to protect both the synthesizer and the charac- terizer of crystalline samples. The committee urges that policies be established that foster access to samples but also protect the intellectual contributions of the researchers who discover or develop novel crystalline materials. (See Appendix F, âNetwork Policies and Procedures,â for a draft of such policies.) Following on Recommendation 1, the committee urges DOE and NSF, the agencies that now fund the majority of such research, to establish as soon as is practicable a network to increase communication and enhance collaboration among DGCM researchers. one possible Implementation Plan Given the broad goals outlined above, the committee offers the following pos- sible plan to illustrate a path forward to implement these goals. Such a path forward has the potential to achieve far more than the organization and communications structures previously found in industrial research laboratories. A new paradigm of DGCM discovery can be achieved by harnessing the full potential of modern and accessible DGCM synthesis facilities, educational and training opportunities, shared databases, and improved measurement capability. Through a crystalline materials network, all of these elements can be tightly coupled by cyber infra- structure in ways not possible even 10 years ago. The result should be the rapid acceleration of DGCM both to match the growth of measurement science and to accelerate the innovation process for new technologies.
136 Frontiers in C rys ta l l i n e M at t e r Creation of a Crystalline Materials Network The vision of a crystalline materials network is not simply to replace the net- working system lost with the closing of the large industrial research laboratories, but to implement a cutting-edge program that takes full advantage of networking opportunities offered by cyber infrastructure. The model proposed seeks to amplify methods and procedures at present employed in successful DGCM research groups. The hallmark of such groups is the self-organization of social networks built around specific scientific problems. These problems are dynamically changing; in response, collaborations also change over time. The overarching goal of the crystalline materials network would be to enhance the ability for research collaborations to change dynamically in the most produc- tive manner by providing communications channels in both the synthesis and the measurement realms. The network could build and maintain a âmaterials develop- ment highwayâ that would enable researchers to collaborate more seamlessly. Thus, it would provide a forum where participants could share growth techniques and areas of expertise, provide information on available samples, disseminate informa- tion on results, and post sample access policies and procedures. Most importantly, the network could facilitate the distribution of samples and provide a searchable database of materials properties. With the extra freedom of information available through a crystalline materials network, however, would come additional responsibilities. These responsibilities would be articulated through the forum of the network. Further, the network would not be directly responsible for administering programmatic funds but would oper- ate in a spirit similar to the user committee of a beam-line sharing facility. While the committee does not intend to prescribe the exact nature of a crystalline materials network, a number of ideas were generated during the committeeâs deliberations that may be of interest. These are documented below in the form of specific pos- sible elements of a crystalline materials network: â¢ DGCM proposal modes: Crystalline materials discovery is often motivated by synthesis experts seeking either a new crystal structure or a crystal comprising a new combination of elements or molecules. Motivation can also come from researchers seeking larger crystals, samples with Âelemental substitution, or samples with very high purity. It may also come from researchers seeking novel properties such as materials for energy-related applications. Both grower-motivated and measurer-motivated approaches should be accommodated in the organization of a future crystalline m Â aterials network. âI the crystal grower-motivated proposal mode: The originating idea for n growing either a new compound or a high-purity single crystal of a
Conclusions and R e c o m m e n dat i o n s 137 known compound is developed by the synthesis scientist. This can be viewed as similar to research directed toward establishing new mea- surement capability by a resident scientist in a large user facility. For instance, a new spectroscopic tool developed by a resident neutron- s Â cattering scientist would be made available to guest scientists. Similarly, when a new compound was synthesized or a higher-quality crystal of an existing compound was made, this would be made available, by pro- posal, to the external community. â n the measurer-motivated proposal mode: A measurement scientist I would propose the synthesis of a novel compound, an existing com- pound, or a variation of an existing compound, such as a site-dilution series, to be grown by a particular expert in the network. The proposal would be handled in a manner similar to that for dealing with an exter- nal proposal for a user facility. The technical part of the proposal would consist of a short description of the desired compound and a descrip- tion of the planned measurement and/or desired property. In order to manage the competitive nature of measurements, the samples would be disbursed with a stipulated understanding of exclusivity and confi- dentiality of measurement. Usually the measurer desires an exclusive right to a particular compound for a period of time that encompasses publication of the results in order to establish priority of discovery. This dormancy period might extend up to from 6 months to 1 year from publication. However, one can imagine rare circumstances when it is desirable for two researchers to perform, by consent of the grower, the same measurement on a given compound. The important point is that the grower would own the samples, subject to network policies and procedures, and would exert control over their distribution. As discussed above, coauthorÂship and acknowledgment of crystal growers and characterizers are essential and would be developed as part of the policies and procedures for access to the network. â¢ Proposal mechanism: A proposal to access or grow a particular sample would describe the type of measurement to be performed and indicate the principal investigators involved. Requesting a sample from the net- work would be tantamount to requesting research support funding; thus c Â riteria usual for making such decisions would be applied. The main c Â riteria for a successful proposal are the quality of the idea, the Âability of the proposer to execute the research, the past performance of the pro- poser, and of course the capability of the network growers to fulfill the request. Proposals would be held in confidence by a proposal review board established by the network administration.
138 Frontiers in C rys ta l l i n e M at t e r â¢ Oversight: Oversight of the crystalline materials network would be carried out by two bodies: a scientific advisory board and an independent review panel. A scientific advisory board, appointed by the network director or head administrator, would provide advice on all elements of the network to the director, including the policies and procedures for access and for optimizing network impact. In addition, an independent review panel constituted of peers both within and external to the network would be assembled on a regular basis to review the impact of the network and its operating policies and procedures on access, proposal review, and so forth. A report containing the independent review panelâs findings and recom- mendations would be submitted to the funding agencies. â¢ Proposal review: A proposal review board would review crystal growth pro- posals submitted to the crystalline materials network on the basis of criteria of the International Union of Pure and Applied Physics for excellence in research. Feasibility would be reviewed by the crystal grower(s) ârequestedâ by the proposal and the proposal review board. The board would consist of scientists within and external to the network. â¢ Reporting and oversight: The crystalline materials network would issue an annual report of all published research conducted under its auspices. The reported research would include all collaborative activities involving one or more network-affiliated researchers. For collaborations, it is expected that the samples requested would undergo one or more measurements. The results of these measurements would likely be published. However, it is not uncommon for a measurement not to yield publishable results, and in this situation the network would request a brief summary of the measurement(s) attempted or performed and the reason for lack of publication. â¢ Meetings: The crystalline materials network would coordinate meetings to organize scientific activities, to review proposals, to hold workshops and summer schools, and to address administrative issues associated with archives and databases. â¢ Crystal archive: The crystalline materials network would create a virtual archiveâa searchable database listing samples in storage at any loca- tionâthat would consist of the significant collection of crystals that network synthesis scientists already possess in storage. Samples would be added to the database at the discretion of the grower. In addition, it is expected that crystals grown with network support would eventually be placed in the archiveâsay after the dormancy period discussed in the first item in this list. The archive would be accessible by means of downloadable spreadsheets that would be continually updated by the network. These spreadsheets would provide a brief description of the samples available from the archive. Archived samples would be available
Conclusions and R e c o m m e n dat i o n s 139 by proposal directly from the grower. In addition, the network would maintain primary sample sources constituted from legacy collections. â¢ Materials property database: Databases have greatly enhanced the Âability to access published information. The effectiveness of databases is no Âbetter, however, than the selection of key words by authors upon publication of scientific results. In addition to the present lack of standardization of key words, key word attributes only extend back in time a couple of decades, thus limiting accessibility to published data. Compendia such as the Landolt-BÃ¶rnstein series attempt to address the need for information on collected materials properties. Such information is not, however, dynami- cally updated and is not easily cross-referenced. Thus, there is a need for a database that is searchable along crystalline materials properties lines, is dynamically updated as new papers are published, is searchable along arbitrary key word combinations, and is free to the DGCM community. It is envisioned that the crystalline materials network would administer this database. The committee believes that such a database would change the way that crystalline materials research is performed by enabling searches not now possible and by reducing unnecessary duplication of work that is essentially clerical. Large Centers of Expertise This subsection lists selected important characteristics of large DGCM centers of expertise and provides suggestions for their focus and potential contribution to an overall national effort. It also enumerates a few of the challenges and opportuni- ties that large DGCM research centers could be expected to address. â¢ State-of-the-art facilities: Entire classes of important materials are not at present being explored in the United States owing to a general lack of large-scale facilities for synthesis. These include facilities for growth involv- ing toxic materials, growth under extreme conditions, growth with in situ advanced characterization tools, and growth of very large, ultrapure crys- tals. Large DGCM centers could be established at national laboratories where the support staff, infrastructure, large-scale characterization facilities, and environmental, health, and safety procedures are well established. â¢ Scope of centers: Each center would be most productive if its research port- folio focused on several high-impact thematic areas of research, driven by selected classes of materials synthesis. Selection of these themes would be determined through extensive input from the scientific and industrial communities and would be subject to renewal by review on a regular basis to ensure continued optimal impact.
140 Frontiers in C rys ta l l i n e M at t e r â¢ Scale of centers: It would be critical that the large centers sustain a âcriti- cal massâ of researchers in each of the chosen thematic areas. Typically, a team of 5 to 10 staff would provide the full breadth of required skills, from synthesis to characterization and theory, for advancing the state of the art. Since a center might pursue three or four integrated themes, the commit- tee envisions that any one center would incorporate up to 30 to 40 staff members, selected on the basis of their research area and demonstrated skill set. â¢ Multidisciplinary environment: While most laboratories can provide a m Â odicum of measurement feedback, large centers have the capability to couple DGCM research to large-scale measurement capability for rapid information feedback. Large centers would also combine experimental activities with theory and computational efforts. â¢ Addressing large-scale problems: Many research challenges in DGCM cannot be addressed by small university research groups. Such challenges involve, for example, very long timescale growth runs, the growth of very large samples, or growth combined with complex diagnostic methods. These topics would be the natural domain of large DGCM centers. â¢ Advancing the state of the art in DGCM: Large centers would have as part of their mission the development of new DGCM techniques. Technique development normally involves a significant amount of engineering and infrastructure and long development timescales, none of which is feasible at small centers. â¢ Promoting collaborative work with U.S. industry: An important role of some DGCM centers would be to provide a link to industry. These centers would address basic research synthesis projects of importance to an industrial sector in order to augment applied research and development activities in specific companies. The centers would provide a vehicle for collabora- tive research between industrial and center-based researchers, for example through visitor programs, to grow desired materials. There are several existing models for such an industry-oriented center that can be evaluated and adapted. An example is the Crystal Growth Laboratory (CGL) affiliated with the Fraunhofer Institute for Integrated Systems and Device Technol- ogy in Erlangen, Germany. Started in 1996, CGL has maintained general crystal growth and assessment capabilities and has also developed sev- eral focal areas of expertise, including a specialization in the development of computer simulation. Its programs are regularly assessed and modi- fied on the basis of its industrial partnersâ needs. Given a similar funding model, namely, cost recovery, the industry-oriented center contemplated here would develop areas of expertise based on directions of interest to its industrial partners. As part of the crystalline materials network recom-
Conclusions and R e c o m m e n dat i o n s 141 mended in this study, it also is expected that opportunities for industrial research would arise that would involve other centers in the network. â¢ Growth of high-purity, known materials that have no commercial source of supply: In new fields of study, commercial sources of raw materials are often not available in the necessary purity or crystal size for sensitive physi- cal measurements. Large centers would have, as part of their distributed portfolio, the mission to perform noncommercial applied crystal growth for basic research needs. â¢ Summer schools: A critical part of a new DGCM initiative would be to c Â reate summer schools for the purpose of education and networking among members of the DGCM research community. In addition to f Â ormal instruction, such schools would provide hands-on training. The large DGCM centers are natural organizing centers for such schools. (See Appendix G, âEducational Role of the Discovery and Growth of Crystalline Materials Centers of Expertise,â for more information.) University-Based Programs or Centers In addition to large centers devoted to DGCM, increased university-based efforts in DGCM are important to a comprehensive DGCM initiative. Geographi- cally diverse university-based efforts provide a unique approach to DGCM activities. Some of the important operational characteristics for university-based programs are listed below, along with their contribution to the education and training of the next generation of DGCM experts. â¢ Multidisciplinary research: Advances in crystalline matter discovery are often initiated at the frontiers where disciplines meet. The university envi- ronment provides the ideal setting to encourage interdisciplinary efforts in chemistry, physics, and biology. The success of DGCM depends on u Â niversity-based initiatives. Nevertheless, universities must find ways to lower the barriers to interdisciplinary activities and work to provide a natural home for synthesis researchers. â¢ Multidisciplinary emphasis: As mentioned above, efficient DGCM requires tight feedback with measurement. With modern capability for measure- ment of key properties such as crystal structure, electrical transport, and magnetic response, such rapid feedback would be readily achievable, even in smaller centers of expertise. â¢ Shared equipment or facilities: For DGCM centers to thrive in a university environment, access to both synthesis and measurement facilities should be treated as shared facilities rather than as captive capabilities of an individual faculty member or principal investigator.
142 Frontiers in C rys ta l l i n e M at t e r â¢ Support for operations and technicians: DGCM activities are extremely labor intensive, requiring high levels of support for operations, includ- ing infrastructure maintenance, raw materials, and technical support. This support is justified on the programmatic level because the materials synthesized by principal investigators associated with a university center should be made available to a larger scientific cohort than that of a single principal investigator. â¢ Specific courses in DGCM: For DGCM to be a bona fide intellectual endeavorâthat is, embraced by university administrators and colleaguesâ it must support a curriculum by which future generations of DGCM researchers are trained. â¢ Research programs as training grounds: While informal or postgraduate training can occur in national laboratories, as it did in industry, the formal aspect of DGCM training should occur in a university setting where syn- thetic projects are developed in the course of graduate work. Summary The discovery of new crystalline materials and the growth of single crystals with carefully tailored properties have very high scientific and technological impact. The convergence of technology streams and the rise of the global economy have resulted in major changes in the U.S. research landscape in this arena, leaving scientists and engineers in the United States severely constrained by inadequate supplies of crystals for scientific research and technology development. As a result, scientists and engineers in DGCM in the United States are at a competitive disÂ advantage compared to scientists and engineers in selected countries in Europe and Asia. Addressing this issue is important to U.S. economic competitiveness and national security. Based on an analysis of the needs, along with the characteristics of the most effective practices in DGCM, the Committee for an Assessment of and Outlook for New Materials Synthesis and Crystal Growth has developed a series of recommendations to strengthen greatly the U.S. capability in the synthesis of new materials and crystal growth. The set of activities in the proposed approach would fit well within the mission of several agencies, including DOE, NSF, DOD, and DOC (National Institute of Standards and Technology) and is well matched to the anticipated growth in these programs under the authorized research funding increases to foster U.S. competitiveness.