Condensed Matter Physics Theory
From the left, first column: (upper figure) Cut plane view of electron bonding charge densities of an iron-phosphorus compound obtained from ab initio calculations, and (lower figure) scanning electron micrograph of fracture surface of ductile amorphous steel showing network of plastic deformation zones. Second column: Pole figures of a (002) MnAl thin film deposited on a MgO substrate. Third column: (upper) The magnetic strip domain structure of MnAl thin film revealed by Magnetic Force Microscopy image. (Lower) The detailed magnetic parallel strip domains showing the width is ~10 nm. Fourth column: Color contour map of the strongly anisotropic spin resonance neutron scattering intensity in the momentum space obtained from superconducting FeTe0.5Se0.5 whose crystal structure is shown in the inset.
Condensed matter physics seeks to understand the striking new physical properties that may emerge when very large numbers of atoms or molecules organize into solids or liquids. Research in this area has led to fundamental breakthroughs in our understanding of metals, semiconductors and superconductors, as well as to the inventions of the transistor, diode laser, and integrated circuit. Condensed matter physics thus comprises the technological underpinning for the entire modern computer and communications industry. For these reasons, worldwide, this branch of physics commands the largest number of researchers, who work in academic institutions, major industrial and government laboratories, and small entrepreneurial enterprises. The problems addressed by condensed matter physicists are often interdiscplinary in nature, affecting a number of other scientific fields including chemistry, biology, electrical engineering, and materials science. The University of Virginia maintains a diverse and vigorous research program in both experimental and theoretical condensed matter physics.
The experimental condensed matter research groups at UVa explore the structural, optical, electronic, and magnetic properties of different types of solids ranging from amorphous to crystalline systems with unusual properties. Activities include the synthesis and characterization of metallic glasses, quasicrystals, colossal magnetoresistive manganites and high temperature superconductors, measurements of electronic and magnetic properties of new intermetallic compounds, characterization of static and dynamic lattice effects in oxides, intermetallic alloys and martensites using the pair density function analysis, study of the microscopic processes at the interface of two relatively sliding materials as well as inside metals and crystals during plastic deformation, study of phase transitions, measurement of magnetic and quantum correlation effects in heavy fermion and high-temperature superconductors, scanning-probe and optical studies of new semiconductor alloys, studies of wetting and adsorption on crystal surfaces, and development of far-infrared applications of semiconductors and superconductors. The condensed matter community at UVa has access to a variety of cryogenic facilities capable of scanning temperatures from as low as 15 mK to room temperature, several high-field magnets, a quantum-interference magnetometer, different scanning-probe instruments such as scanning tunneling, force, and optical microscopes, various vacuum thin-film deposition and etching systems, and a range of microwave and millimeter-wave analytic instruments. In addition, many research projects work closely with Electrical Engineering and Materials Science Departments, using facilities such as a photolithography lab and X-ray diffraction and elec-tron-beam microscopes, as well as national labs where high magnetic fields sources are available. The group also performs research at national and international neutron and x-ray facilities and carries out high precession measurements on the atomistic properties of materials particularly under high pressure.
Theoretical condensed matter physicists at UVa try to arrive at a quantitative description of many unusual properties observed in novel materials and fluids. Such research includes an investigation into what makes the new generation of high-temperature superconductors work as they do, solving model problems like quantum spin chains which are believed to contain the features of newly synthesized low-dimensional metals and magnets. Studies of the structure of magnetic vortices in superconductors and the interactions that bind atoms and molecules to solid surfaces are also underway. For example, the point-contact tunneling amplitude for the fractional quantum Hall effect was recently exactly computed.
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- "Superconductivity in transition metal doped MoB4", J. W. Simonson, D. Wu, S. J. Poon, and S. A. Wolf, J. Superconductivity and Novel Magnetism 23, 1557 (2010).
- "Compressive plasticity and toughness of a Ti-based bulk metallic glass", X. J. Gu, S. J. Poon, G. J. Shiflet, and J. J. Lewandowski, Acta Materialia 58, 1708 (2010).
- "Relaxation dynamics of the metal-semiconductor transition in VO2 thin films", J. H. Claassen, J. W. Lu, K. G. West, S. A. Wolf, Appl. Phys. Lett. 96, 132102 (2010).
- "Transport phase diagram for superconducting thin films of tantalum with homogeneous disorder", Y. Z. Li, C. L. Vicente, J. Yoon, Phys. Rev. B 81, 020505 (2010).
- "Study of SF6 adsorption on graphite using infrared spectroscopy", P. Thomas, Y. Xia, D. A. Boyd, T. A. Hopkins, G. B. Hess, J. Chem. Phys. 131 (12), 124709 (2009).
- "Spin-lattice order in frustrated ZnCr2O4", S. Ji, S.-H. Lee, C. Broholm, T. Y. Koo, W. Ratcliff, S-W. Cheong, P. Zschack, Phys. Rev. Lett. 103, 037201 (2009).
- "Magnetic field-induced phase transitions in a weakly coupled s = 1/2 quantum spin dimer system Ba3Cr2O8", M. Kofu, H. Ueda, H. Nojiri, Y. Oshima, T. Zenmoto, K. C. Rule, S. Gerischer, B. Lake, C. D. Bastista, Y. Ueda, S.-H. Lee, Phys. Rev. Lett. 102, 177204 (2009).
- "Hidden quantum gap state in the static stripe phase of La2-xSrxCuO4", M. Kofu, S.-H. Lee, M. Fujita, H.-J. Kang, H. Eisaki, K. Yamada, Phys. Rev. Lett. 102, 047001 (2009).
- "Weakly coupled s = 1/2 quantum spin singlets in Ba3Cr2O8", M. Kofu, J.-H. Kim, S. Ji, S.-H. Lee, H. Ueda, Y. Qiu, H. J. Kang, M. Green, Y. Ueda, Phys. Rev. Lett. 102, 037206 (2009).
- "Formation of local electric dipoles with no unique polar axis in Tb3Fe5O12", Despina Louca, K. Kamazawa, T. Proffen, Phys. Rev. B 80, 214406 (2009).
- "High Capacity Hydrogen Absorption in Transition Metal Ethylene Complexes: consequences of nanoclustering", A. B. Phillips and B. S.Shivaram, Nanotechnology 20, 204020 (2009).
- "Colloquium: Electron-lattice interaction and its impact on high Tc superconductivity, V. Z. Kresin and S. A. Wolf, Rev. Mod. Phys. 81, 481 (2009).
- "Properties of vanadium and tantalum granular oxide-metal tunnel junction fabricated by electrochemical anodization", W. Fan, D. Kirkwood, J. Lu, S. A. Wolf, Appl. Phys. Lett. 95, 232110 (2009).
- "Multiple-Trap Correlations in the Room-Temperature Random Telegraph Signal of a Carbon Nanotube Field-Effect Transistor". Tsz Wah (Jack) Chan , Brian Burke , Kenneth Evans , Keith Williams, Smitha Vasudevan, Mingguo Liu , Joe Campbell , Avik Ghosh, Phys. Rev. B 80, 033402 (2009).
- "Infrared spectroscopic study of C2F6 monolayers and bilayers on graphite", T. A. Hopkins, D.A. Boyd, Y. Xia, G. M. Shifflett, F. M. Hess, and G. B. Hess, J. Chem. Phys. 128 (15), 154714 (2008).
- "External magnetic field effects on a distorted kagome antiferromagnet", J.-H. Kim, S. Ji, S.-H. Lee, B. Lake, T. Yildirim, H. Nojiri, K. Habicht, Y. Qiu, K. Kiefer, Phys. Rev. Lett. 101, 107201 (2008).
- "Field-induced antiferromagnetism and competition in the metamagnetic state of terbium gallium garnet", K. Kamazawa, Despina Louca, R. Morinaga, T. J. Sato, Q. Huang, J. R. D. Copley, Y. Qiu, Phys. Rev. B 78, 064412 (2008).
- "(Zr,Hf)Co(Sb,Sn) half-Heusler phases as high-temperature (>700 oC) p-type thermoelectric materials", S. R. Culp, S, J, Poon, V. Ponnambalam, J. Edwards, and T. M. Tritt, Appl. Phys. Lett. 93, 022105 (2008).
- "Poisson's ratio and intrinsic plasticity in metallic glasses", S. J. Poon, A. W. Zhu, and G. J. Shiflet, Appl. Phys. Lett. 92, 261902 (2008).
- "High Capacity Hydrogen Absorption in Transition Metal Ethylene Complexes Observed via Nanogravimetry", A. B. Phillips and B. S.Shivaram, Phys. Rev. Lett. 100, 105505 (2008).
- "Very large anisotropy in the dc conductivity of epitaxial VO2 thin films grown on (011) rutile TiO2", J. W. Lu, K. G. West, S. A. Wolf, Appl. Phys. Lett. 93, 262107 (2008).
- "Deep-UV Pattern generation in PMMA", Brian G Burke, Timothy J Herlihy Jr, Andrew B Spisak and Keith A Williams, Nanotechnology 19, 215301 (2008).
- "Quantum spin liquid states in the two dimensional kagome antiferromagnets, ZnxCu4-x(OD)6Cl2", S.-H. Lee, H. Kikuchi, Y. Qiu, B. Lake, Q. Huang, K. Habicht, K. Kiefer, Nature Materials 6, 853 (2007).
- "Spin-lattice instability to a fractional magnetization state in the spinel HgCr2O4", M. Matsuda, H. Ueda, A. Kikkawa, Y. Tanaka, K. Katsumata, Y. Narumi, T. Inami, Y. Ueda, S.-H. Lee, Nature Physics 3, 397 (2007).
- "Characterization of Nanostructures During Growth Using a Quartz Monitor", A.B. Phillips and B.S. Shivaram, Appl. Phys. Lett. 91, 153109 (2007).
- "Spin Incommensurability and Two Phase Competition in Cobaltites", D. Phelan, Despina Louca et al., Phys. Rev. Lett. 97, 235501 (2006).
- "Nano-magnetic droplets and implications to orbital ordering in La1-xSrxCoO3", D. Phelan, Despina Louca et al., Phys. Rev. Lett. 96, 027201 (2006).
- "Origin of nonlinear transport across the magnetically induced superconductor-metal-insulator transition in two dimensions", Y. Seo, Y. Qin, C. L. Vicente, K. S. Choi, J. Yoon, Phys. Rev. Lett. 97, 057005 (2006).