Wake Forest Physics
|
Condensed Matter PhysicsThe area of major concentration is condensed matter physics, which includes the work of experimentalists, David Carroll, Oana Jurchescu, and Richard T. Williams, and theorists Natalie A. W. Holzwarth, William C. Kerr, G. Eric Matthews, and Timo Thonhauser.
While
the focus is basic research, the department is extensively involved in laser
processing of materials. Richard Williams, Eric
Matthews, and their students have produced and characterized
thin film high-Tc superconductors of good quality. Applied research in laser
planarization and bonding of metals and in photoablation of polymers is conducted
by the Williams group. Oana Jurchescu’s group focuses on investigation and development of organic materials and devices for nano and macroelectronics applications. The group is part of the Center for Nanotechnology and Molecular Materials, one of the Research Institutes at Wake Forest University. The research in Organic Electronics group covers a variety of fundamental and applied topics on materials and devices for future electronics. The interest in this topic is motivated by the potential of organic (plastic) electronics to greatly impact the future semiconductor industry by low-cost and high diversity. The Organic electronics program consists of exciting and interdisciplinary topics of research, providing opportunities for both undergraduate and graduate involvement. For more info please visit: http://www.wfu.edu/~jurcheod/research/ William Kerr leads a group in the study of statistical physics. The research in this group concentrates on systems in which nonlinearity is the dominating feature. In some situations nonlinearity produces highly organized behavior, which is described by solitons. In other cases nonlinearity produces seemingly random behavior, which is often characterized as chaos. This group studies these phenomena by computer simulations. Their emphasis recently has been on studying soliton mechanisms underlying the dynamics of first- and second-order phase transitions. The experimental impetus for these studies comes from structural phase transitions in solids. The major issues here include the existence or nonexistence of soft modes and of precursor fluctuations of the product phase occurring within the parent phase. Such fluctuations would be described by nonlinear partial differential equations similar to the sine-Gordon or nonlinear Schrodinger equations, perhaps with extensions which describe bond anharmonicity in addition to the site anharmonicity. In addition to these important physical questions, employing computer simulation to study these problems raises a set of methodological problems. These deal with writing computer codes that efficiently use vector supercomputer architectures and with developing methods of analysis, including visualization schemes, that effectively extract the important physical processes occurring in the system from the large volume of numbers produced by the simulations . Natalie Holzwarth, Rick Matthews, and Timo Thonhauser lead research groups that conduct first principles computer modeling of electronic and structural properties of materials. They work closely with experimental groups on a variety of projects including the study of new materials, surfaces, and defects in crystals. Most of the modeling is based on density functional theory, developed by Walter Kohn and his collaborators in 1964 (for which he shared the 1998 Nobel prize in Chemistry). The work is divided between a focus on code and algorithm development and a focus on materials physics. The group has developed some general purpose electronic structure code which is made available on the web at http://pwpaw.wfu.edu. Some of the recent materials studied by the group include scintillating crystals such as PbWO4, F-centers in alkali halide crystals, and surface states related to photoemission experiments performed in Richard Williams' lab. Other projects include studies of molecular crystals such the one illustrated in the figure and Li ion battery materials such as the cathode materials (FeLiPO4, FePO4) and electrolytes (Li3PO4).
|
Page Links
|
![]() |
||
![]() 100 Olin Physical Laboratory Wake Forest University Winston-Salem, NC 27109-7507 Phone: (336) 758-5337, FAX: (336) 758-6142 E-mail: wfuphys@wfu.edu |