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SLAC National Accelerator Laboratory, originally named the Stanford Linear Accelerator Center, is a federally funded research and development center in Menlo Park, California, United States. Founded in 1962, the laboratory is now sponsored by the United States Department of Energy and administrated by Stanford University. It is the site of the Stanford Linear Accelerator, a 3.2 kilometer (2-mile) linear accelerator constructed in 1966 that could accelerate electrons to energies of 50 GeV.
In physics, the Kondo effect describes the scattering of conduction electrons in a metal due to magnetic impurities, resulting in a characteristic change i.e. a minimum in electrical resistivity with temperature. The cause of the effect was first explained by Jun Kondo, who applied third-order perturbation theory to the problem to account for scattering of s-orbital conduction electrons off d-orbital electrons localized at impurities. Kondo's calculation predicted that the scattering rate and the resulting part of the resistivity should increase logarithmically as the temperature approaches 0 K. Experiments in the 1960s by Myriam Sarachik at Bell Laboratories provided the first data that confirmed the Kondo effect. Extended to a lattice of magnetic impurities, the Kondo effect likely explains the formation of heavy fermions and Kondo insulators in intermetallic compounds, especially those involving rare earth elements such as cerium, praseodymium, and ytterbium, and actinide elements such as uranium. The Kondo effect has also been observed in quantum dot systems.
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References
- ↑ DOE/SLAC National Accelerator Laboratory (2013-11-21). "Will 2-D tin be the next super material?". Sciencedaily.com . Retrieved 2014-01-10.
- ↑ Garcia, J. C.; de Lima, D. B.; Assali, L. V. C.; Justo, J. F. (2011). "Group IV Graphene- and Graphane-Like Nanosheets". J. Phys. Chem. C. 115: 13242. doi:10.1021/jp203657w.
- ↑ "Will 2-D tin be the next super material?". Phys.org. 21 November 2013. Retrieved 2014-01-10.
- ↑ Xu, Yong; Yan, Binghai; Zhang, Hai-Jun; Wang, Jing; Xu, Gang; Tang, Peizhe; Duan, Wenhui; Zhang, Shou-Cheng (2013-09-24). "Large-Gap Quantum Spin Hall Insulators in Tin Films". Physical Review Letters. 111 (13): 136804. arXiv: 1306.3008 . doi:10.1103/PhysRevLett.111.136804. ISSN 0031-9007. PMID 24116803. S2CID 11310025.
- ↑ Singh, Ritu (November 24, 2013). "Tin could be the next super material for computer chips". Zeenews .
- ↑ Markoff, John (January 9, 2014). "Designing the Next Wave of Computer Chips". New York Times . Retrieved January 10, 2014.
- ↑ "Will 2-D Tin be the Next Super Material?" (Press release). Stanford University: SLAC National Accelerator Laboratory. November 21, 2013.