Ward P. Beyermann
Ward P. Beyermann
Department of Physics & Astronomony
- Experimental condensed matter physics
Ward Beyermann, Associate Professor of Physics, specializes in the transport and thermodynamic properties of highly correlated electronic condensed matter systems. These include materials where the strong interactions between the electrons lead to unusual properties at low temperatures. Specific heat and resisitivity are measured down to millikelvin temperatures and in high magnetic fields. Some of the systems investigated include lanthanide and actinide intermetallic compounds, lanthanide intermetallic borocarbides, and carbon-fullerene materials.
Strong many-body correlations play an important role in certain intermetallic compounds that contain 4f and 5f moments. The interactions between the localized felectrons and the conduction electrons renormalize the relevant energy scales and modify the thermodynamic and transport properties at low temperatures. Depending on the magnitude of the interactions, these compounds are referred to as either "heavy-fermion" or "mixed-valent" systems. The strong correlations are also responsible for unusual superconducting and magnetic ground states in some materials. Studying properties like the specific heat and transport in prototypical and recently discovered materials is the main trust of this research. These properties are measured at temperatures as low as ~50 mK, and some experiments are performed in magnetic fields as high as 50 T at the National High Magnetic Field Laboratory. Neutron scattering is also used to investigate magnetic e xcitations in these systems in collaboration with the Los Alamos Neutron Scattering Center. Rare-earth and intermetallic atomic substitutions help us investigate the interplay between magnetic, superconducting, and normal state interactions.
Finally, the properties of the new carbon fullerene compounds (e.g. C60, K3C60 and nanotubes) are being investigated. Specific-heat experiments are being performed to study the intra-vibrational, inter-vibrational, and rotational modes which are unique to these systems.
Ph.D., 1998, University of California, Los Angeles
- B. Yoo, Y. Rheem, W. P. Beyermann and N. V. Myung, "Magnetically assembled 30 nm diameter nickel nanowire with ferromagnetic electrons," Nanotechnology 17, 2512 (2006).
- F. X. Xiu, Z. Yang, L. J. Mandalapu, J. L. Liu, W. P. Beyermann, "p-type ZnO films with solid-source phosphorus doping by molecular-beam epitaxy," Applied Physics Letters 88, 052106 (2006).
- S. Li, M. C. De Andrade, E. J. Freeman, C. Sirvent, R. P. Dickey, A. Amann, N. A. Frederick, K. D. D. Rathnayaka, D. G. Naugle, S. L. Bud'ko, P. C. Canfield, W. P. Beyermann, M. B. Maple, "Physical properties of Lu1-xYbxNi2B2C," Philosophical Magazine 86, 3021 (2006).
- J. P. Ge, Y. X. Hu, M. Biasini, C. L. Dong, J. H. Guo, W. P. Beyermann, Y. D. Yin, "One-step synthesis of highly water-soluble magnetite colloidal nanocrystals," Chemistry-A European Journal 13, 7153-7161 (2007). Y. Rheem, B.-Y. Yoo, W. P. Beyermann and N. V. Myung, "Magnetotransport studies of a single nickel nanowire," Nanotechnology 18, 015202 (2007).
- Q. C. Zhang, X. H. Bu, Z. Lin, M. Biasini, W. P. Beyermann, P. Feng, "Metal-complex-decorated homochiral heterobimetallic telluride single-stranded helix," Inorganic Chemistry 46, 7262 (2007).
- Y. Rheem, B.-Y. Yoo, W. P. Beyermann and N. V. Myung, "Magneto-transport studies of single ferromagnetic nanowire," Phys. Stat. Sol. (a) 204, 4004 (2007).
- J. P. Ge, Y. X. Hu, M. Biasini, W. P. Beyermann, Y. D. Yin, "Superparamagnetic magnetite colloidal nanocrystal clusters," Angewandte Chemie-International edition, 46, 4342 (2007).
- Y. Rheem, B.-Y. Yoo, W. P. Beyermann and N. V. Myung, "Synthesis and magnetotransport studies of single nickel-rich NiFe nanowire," J. Phys. D: Appl. Phys. 40, 7267 (2007).
- Y. Rheem, B.-Y. Yoo, W. P. Beyermann and N. V. Myung, "Electro- and magneto-transport properties of a single CoNi nanowire," Nanotechnology 18, 125204 (2007).
- Z. Yang Z, J. L. Liu, M. Biasini, W. P. Beyermann, "Electron concentration dependent magnetization and magnetic anisotropy in ZnO:Mn thin films," Applied Physics Letters 92, 042111 (2008).
- J. R. Morales, J. E. Garay, M. Biasini, W. P. Beyermann, " Magnetic characterization of bulk nanostructured iron oxides," Applied Physics Letters 93, 022511 (2008).
- Z. Yang, M. Biasini, W. P. Beyermann, M. B. Katz, O. K. Ezekoye, X. Q. Pan, Y. Pu, J. Shi, Z. Zuo, J. L. Liu, "Electron carrier concentration dependent magnetization and transport properties in ZnO:Co diluted magnetic semiconductor thin films," (in press)
- Z. Yang, W. P. Beyermann, M. B. Katz, O. K. Ezekoye, Z. Zuo, Y. Pu, J. Shi, X. Q. Pan, J. L. Liu, "Microstructure and transport properties of ZnO:Mn diluted magnetic semiconductor thin films," Journal of Applied Physics (under peer-review).
- P. Glancy and W. P. Beyermann, "Dielectric response of suspended nucleotides at terahertz frequencies," to be published (2008).