CARNEGIE/DOE ALLIANCE CENTER Year Four Annual Report
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CARNEGIE/DOE ALLIANCE CENTER A Center of Excellence for High Pressure Science and Technology Supported by the Stewardship Science Academic Alliances Program of DOE/NNSA Year Four Annual Report December 2007 Russell J. Hemley, Director Ho-kwang Mao, Associate Director Stephen A. Gramsch, Coordinator Carnegie/DOE Alliance Center (CDAC): A CENTER OF EXCELLENCE FOR HIGH PRESSURE SCIENCE AND TECHNOLOGY YEAR FOUR ANNUAL REPORT 1. Overview 1.1 Mission of CDAC 1 1.2 Highlights from Year 4 2 2. Scientific Progress 2.1 High P-T Phase Relations and Structures 5 2.2 P-V-T EOS Measurements 12 2.3 Phonons, Vibrational Thermodynamics and Elasticity 15 2.4 Plasticity, Yield Strength and Deformation 20 2.5 Electronic and Magnetic Structure and Dynamics 23 2.6 High P-T Chemistry 28 3. Education, Training, and Outreach 3.1 CDAC Graduate Students and Post-doctoral Fellows 36 3.2 CDAC Collaborators 41 3.3 Undergraduate Student Participation 47 3.4 DC Area High School Outreach 48 3.5 2007 Stewardship Science Academic Allliances (SSAA) Program Symposium 49 3.6 SMEC 2007: Study of Matter at Extreme Conditions 52 3.7 Pressure Callibration Workshop 54 3.8 Visitors to CDAC 55 3.9 High Pressure Seminars 57 4. Technology Development 4.1 High P-T Experimental Techniques 59 4.2 Facilities at Brookhaven, LANSCE, and Carnegie 60 5. Interactions with NNSA/DP Laboratories 5.1 Overview 64 5.2 Academic Alliance and Laboratory Collaborations 65 6. Management and Oversight 6.1 CDAC Organization and Staff 66 6.2 CDAC Oversight 67 7. Plans for Year 5 and Beyond 7.1 Scientific and Educational Focus 68 7.2 Implementation of CDAC Phase II 68 7.3 HPCAT Upgrade 72 Appendix I CDAC Publications and Presentations for Year 4 74 Appendix II CDAC Synchrotron Users/Experiments (APS and NSLS) for Year 4 101 References 116 1. OVERVIEW 1.1 Mission of CDAC A thorough knowledge of material properties at high pressure and temperature is critical to the mission of the National Nuclear Security Administration in the support of science-based stockpile stewardship1. This program covers a broad range of problems and materials at multiple scales – d- and f-electron elements and alloys, low-Z molecular compounds, energetic materials and detonation products, dense hydrogen, metal oxides and hydrides and bulk materials as well as composites and interfaces. Information on material behavior in crystalline, liquid, and amorphous phases, phase transitions, equations of state (EOS), phonon dynamics, elasticity and plasticity, electronic and magnetic structures, and chemical reactions likewise are key issues in the broad area of material properties under extreme conditions, as are accurate descriptions of matter in transient, ultra-high density states. In the long term, addressing these problems also requires the training of the next generation of scientists in academia and the national labs. The training of students in turn requires regular access to state-of-the-art facilities that are not readily accessible to research groups in the NNSA Labs or in academic groups. The Carnegie/DOE Alliance Center – CDAC – was created to address these critical needs. New developments and opportunities on a broad range of fronts in science, technology, and training, as well as in the infrastructure within NNSA, require a Center-like approach. Having now completed its fourth year, CDAC continues to support the NNSA mission in these key areas of scientific research and training. The successes of our first three years allowed us to expand and bring a broader range of universities into the alliance, and these successes have continued with a group of 11 Academic Partners. CDAC is managed by Russell Hemley (Director), Ho-kwang Mao (Associate Director), and Stephen Gramsch (Coordinator). CDAC consists of six formal academic partners together with Carnegie: Princeton University (Tom Duffy), University of Chicago (Dion Heinz), University of Illinois (Dana Dlott), University of Alabama - Birmingham (Yogesh Vohra), University of California - Berkeley (Hans-Rudolf Wenk), and California Institute of Technology (Brent Fultz). At the beginning of Year 4, five new academic partners joined the CDAC effort: New Mexico State University (Kanani Lee), Florida International University (Surendra Saxena), Texas Tech University (Yanzhang Ma), University of Nevada - Reno (Dhanesh Chandra), and Arizona State University (Jeffrey Yarger). Scientists at the national labs (CDAC Laboratory Partners) continue to benefit from the availability of beam time and technical training and the high P-T technique development taking place at HPCAT, the dedicated high-pressure Figure 1. CDAC personnel from our Academic Partner institutions. synchrotron x-ray facility at the Advanced Photon Source (APS), of which CDAC is a member. Laboratory scientists are also able to take advantage of facilities at Carnegie and the National Synchrotron Light Source, Brookhaven National Laboratory (NSLS), Active interactions also are in place with staff from the Lujan Center at LANSCE (Los Alamos National Laboratory) in the development of critically important high P-T neutron scattering capabilities. CDAC also has built an extensive list of collaborators from some 176 institutions worldwide. 1 The field of research on materials at extreme conditions continues to expand with the development of new methodologies, for example, in the overlap of static and dynamic compression experiments and the unprecedented accuracy needed for code validation. Despite the remarkable success of HPCAT, the full potential of the techniques it has pioneered is far from realized and requires a multi-beamline approach. Facilities developments within the NNSA/DP Labs such as NIF and ZR are creating new challenges along with the need for input from the academic sector, and advances at neutron sources present new challenges and opportunities for NNSA/DP. CDAC continues to take the lead in enabling development of the next generation of high-pressure techniques, and CDAC personnel are carrying out systematic measurements of a full range of physical and chemical phenomena under extreme conditions. The centerpiece of the CDAC program from the beginning has been the HPCAT facility, which is led by Ho-kwang Mao (Director) and Guoyin Shen (Project Manager), and has been developed for high pressure physics, chemistry and materials science, providing technical developments and critical, state-of-the-art spectroscopic and diffraction tools. All four beamlines have been completed and are accepting general users through the General User Proposal (GUP) program at the APS. At this point, more than 360 different users (i.e., from National Labs and academia) have conducted experiments at the facility to date. The original HPCAT vision of four independently operating experimental hutches has now been realized. High-pressure neutron facilities at LANSCE, synchrotron infrared spectroscopy at the NSLS, and specialized high-pressure facilities at Carnegie complement this effort. At Carnegie, developments continue in the area of high P-T spectroscopy and x-ray crystallography, new cell designs for a variety of experimental measurements, and advances in CVD diamond growth. Experimental work in high-pressure geoscience and planetary science is increasingly carried out with a materials science perspective and therefore provides excellent background for understanding problems in stewardship science and for future work in the NNSA/DP Labs. Interactions with theoretical groups in academia and the National Labs add significantly to the experimental work carried out within the CDAC program. CDAC formally began operations on May 1, 2003 with the first funding year ending January 31, 2004. This report covers activities from the CDAC Academic Partners, Laboratory Partners, and University Collaborators from July 2006-July 2007. Research carried out by National Lab partners, but done outside of the CDAC facilities, is not included. 1.2 Highlights from Year 4 Outreach and Training CDAC continues to make excellent progress in outreach and training, an important part of its mission. The following are highlights, in particular as they relate to student education and training: • Through support of HPCAT, continued to promote the growth of the sector. To date, more than 360 users have carried out experimental work at HPCAT. • Facilitated the growth of the high pressure research community in the US and worldwide through CDAC collaborations. Currently, there are approximately 420 outside collaborators from over 176 institutions in the US and around the world that have collaborated with us on stewardship science-related projects. • Continued to support the Ph.D. thesis work of 18 graduate students at CDAC partner universities and Carnegie. Thus far, 11 graduate students from Academic Partner institutions have received the Ph.D. degree with CDAC support. • Former CDAC graduate student Wendy Mao, following an Oppenhiemer Postdoctoral Fellow appointment at LANL, has just begun a faculty position at Stanford University and will continue to work on stewardship science-related projects. • In partnership with FIU, sponsored the Science of Matter at Extreme Conditions SMEC 2007) Conference in May 2007. The conference featured 41 presentations from groups affiliated with 2 CDAC. CDAC also supported the Workshop on Pressure Calibration at High Temperature, held at Carnegie in January 2007. • Hosted numerous visitors to other CDAC facilities (e.g., Carnegie and NSLS) for training and technique development and continued to foster collaborations with