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CDAC supports graduate student research and training in the area of high pressure materials science, broadly defined. We accept proposals on a continuing basis from faculty interested in joining the CDAC team as academic partners. Student support consists of salary, tuition/fees and some travel to CDAC facilities for experiments. Please send a one-page statement of research interests and plans to Steve Gramsch, CDAC Coordinator by January 16, 2009. 
CDAC high school intern Maneeshika Madduri was a semifinalist in the 2008 Siemens Competition for Math, Science, and Technology with her project on hydrogen complexation studies in crown ethers. Congratulations!
Steven Jacobsen, CDAC Academic Partner from Northwestern (and former Barbara McClintock Postdoctoral Fellow at the Geophysical Laboratory) has been awarded a Packard Fellowship for Science and Engineering. Jacobsen is among 20 scientists selected nationally this year to receive this grant. The funding will support development of Jacobsen’s nano-pulsed GHz-ultrasonic method to study atomic-scale, physical properties of superhard materials targeted for future technological applications
The Carnegie Institution held its annual Summer Scholars Research Symposium on Wednesday, August 6th. The ten students participating in the program this year presented the results of their work for the entire Broad Branch Road campus community. The presentations covered a wide range of topics, including mineral physics, organic geochemistry, astrobiology, petrology, seismology and astronomy.
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Russell Hemley has been elected Honoris Causa Professor for Energetics, Mechanics, Machinery, and Control Systems of the Russian Academy of Sciences (RAS). The academy is the leading scientific body in Russia. Founded in 1724, it is one of the oldest such organizations in the world. The degree is awarded to the most eminent foreign scientists.
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"High Pressure Mineral Physics - A Key to Earth Structure" - A Symposium in Honor of Ronald Cohen Goldschmidt 2009 Davos, Switzerland June 21-26, 2009 More Meetings & Symposia |
| Bigger, Better Diamond Crystals |
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Researchers at the Geophysical Laboratory have developed a technique for improving the properties of diamond, simplifying the process of making high-quality diamond for scientific applications, electronic components, cutting tools, and even quantum computers. The results are published in the current Online Edition of the Proceedings of the National Academy of Sciences.
Impurities and defects in diamond can be purged by annealing, but this can turn diamond to graphite. In order to prevent graphitization, diamond treatments have previously required high pressures (up to 60,000 times atmospheric pressure) during annealing, which is costly and limits the size and quantities of diamond treated. Yufei Meng and colleagues used CVD to grow diamond in their experiments. Unlike other methods, which mimic the high pressures deep within the earth where natural diamond is formed, the CVD method produces single-crystal diamond at low pressure. The resulting diamond, which can be grown very rapidly, have precisely controlled compositions and comparatively few defects. 
The Carnegie team then annealed the diamond at temperatures up to 2000° C using a microwave plasma at pressures below atmospheric pressure. The crystals, which are originally yellow-brown if produced at very high growth rates, turned colorless or light pink. Despite the absence of stabilizing pressure there was minimal graphitization. Using analytical methods such as photoluminescence and absorption spectroscopy, the researchers were also able to identify the specific crystal defects that caused the color changes. In particular, the rosy pink color is produced by structures called nitrogen vacancy (NV) centers, where nitrogen atoms take the place of carbon atoms in the crystal lattice. [Y. Meng, et al., Proc. Nat. Acad. Sci., 105, 17620-17625 (2008)]
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