Peter A. Dowben Charles Bessey Professor, Physics & Astronomy/          Nebraska Center for Materials and Nanoscience E-mail: PDOWBEN1@unl.edu Fax: (402) 472-2879 Office: 255 Behlen Phone: (402) 472-9838 Biographical Summary Research Interests and Capabilities Research Projects Other Links Publication Record Recent Results and Key References Graduate Students (and current affiliations) Post-doc's (and current affiliations)   Biographical Summary: 2002 - present: Charles Bessey Professor, University of Nebraska 1995 - present: Professor of Physics and Graduate Fellow, University of Nebraska 1994 - present: Research Professor of Chemistry, University of Nebraska 1993 - 1995: Associate Prof. of Physics and Graduate Fellow, University of Nebraska 1990 - 1993: Associate Prof. of Physics, Syracuse University, Syracuse, New York 1987 - 1996: Adjunct Prof. of Chemistry, Syracuse University, 1986 - 1993: Member of Solid State Science and Technology Program, Syracuse     University 1984 - 1990: Assistant Prof. of Physics, Syracuse University 1981 - 1983: Scientist with the Fritz-Haber Institut der Max-Planck-Gesellschaft, FRG 1981 - Visiting Scientist to the Department of Physics, University Osnabrueck, FRG 1980 - 1981: Research Assistant to Dr. M. Grunze, Fritz-Haber Institut der Max-Planck     Gesellschaft, and the Free University, Berlin, FRG 1981 - Ph.D. in Physics, Cambridge University Research: Group Personnel Juan Colon-Santana Carolina Ilie Ihor Ketsman Jing Liu David Wisbey Ning Wu Jie Xiao ZhengZheng Zhang  Collaborators at UNL Shireen Adenwalla (Physics) Sina Balkir (Electr. Eng.) Kirill Belashchenko (Physics) Jennifer Brand (Engineering) Susan Hallbeck (Ind. Eng.) Sitaram Jaswal (Physics) Sy-Hwang Liou (Physics) Yaroslov Losovyj (Physics) Jody Redepenning (Chemistry) Brian Robertson (Mech. Eng.) R. Skomski (Physics) Andre Sokolov (Physics) Evgeny Tsymbal (Physics) Julian Velev (Physics) Interests and Capabilities: The major focus of the Dowben group emphasizes the changes in electronic (band) structure across electronic phase transitions in reduced dimensionality. Of interest are ferromagnetism in local moment systems or spatially restricted systems, ferroelectricity and the nonmetal to metal transition. Specific techniques include angle-resolved photoemission, resonant photoemission, inverse photoemission and spin polarized inverse photoemission. Other techniques include spin polarized photoemission, characteristic energy loss, low energy electron diffraction, angle resolved thermal desorption spectroscopy, X-ray photoemission, and Magneto-optic Kerr effect.   Research Projects: (1) Organic and Photolytic organometallic chemical vapor deposition of materials in ultrahigh vacuum for spin valves and spin-tunnel junctions. (2) Orientation, bonding and electronic structure of organic overlayers, organometallic molecular overlayers and molecular magnets. (3) The temperature dependent electronic structure of ferroelectric crystalline molecular films, as a function of metallicity. (4) The spin polarized occupied and unoccupied band structure of local moment ferromagnetic systems as a function of temperature. Funded by the NSF-Chem., NSF Quantum and Spin MRSEC (DMR-0213808), Office of Naval Research, the Defense Threat Reduction Agency and the Nebraska Research Initiative Other Links: Surface Science: www.chem.qmw.ac.uk/surfaces/ www.vacuum.org www.iap.tuwein.ac.at/~werner/data.html www.lasurface.com/accueil/index.php Nanodots and Clusters: (Ward Plummer) www.phys.utk.edu/WPWebSite/ewp_main.htm http://cluster-science.net/service.php www.salford.ac.uk/chemist/nmbres.html www.cnms.ornl.gov/ www.mrsec.unl.edu Synchrotron Light Sources: (SRC) www.src.wisc.edu/ (CAMD) www.camd.lsu.edu/ (NSLS) www.nsls.bnl.gov/ (BESSY) www.bessy.de/ Rare Earth Magnetism: www.wspc.com.sg/books/physics/3851.html (Berlin) orion.physik.hu-Berlin.de Boron Carbide Neutron Detectors: http://www.amazings.com/ciencia/noticias/300702b.html http://www.engr.unl.edu/FINDER/research/index.htm Publication Record: Author of more than 390 articles in refereed journals and books, 22 invited review articles, 21 invited presentations at national and international conferences, and 13 patents. Some papers may be found on the digital commons: http://digitalcommons.unl.edu/physicsdowben   Recent Results and Key References: Limits to Half Metallic Ferromagnetism: P.A. Dowben, J. Phys. Cond. Matter 19 (2007) 31031, and the papers that follow in that issue of JPCM R. Skomski and P.A. Dowben, "Intra-Atomic Aspects of Magnon-Plasmon Interactions", J. Appl. Phys. 99 (2006), 08F508 P.A. Dowben and S.J. Jenkins. "The Limits to Spin-Polarization in Finite-Temperature Half- Metallic Ferromagnets", in Frontiers in Magnetic Materials, edited by Anant Narlikar, Springer Verlag (2005) R. Skomski and P. A. Dowben, "The Finite-Temperature Densities of States for Half-Metallic Ferromagnets", Europhysics Letters 58 (2002) 544-548 P.A. Dowben and R. Skomski, "Are Half-Metallic Ferromagnets Half-Metals? (invited)", Journal of Applied Physics 95 (2004) 7453-7458 Electronic Phase Transitions in Molecular Systems: D.-Q. Feng, D. Wisbey, Y. Tai, Ya. B. Losovyj, M. Zharnikov and P.A. Dowben, "Abnormal Temperature Dependence of Photoemission Intensity Mediated by Thermally Driven Reorientation of a Monomolecular Film", J. Phys Chem. B 110 (2006) 1095-1098 155411 P.A. Jacobson, Luis G. Rosa, C.M. Othon, Kristin Kraemer, A.V. Sorokin, Stephen Ducharme, and P.A. Dowben, "Water Absorption and Dielectric Changes in Crystalline Poly(Vinylidene Fluoride-Trifluoroethylene) Copolymers Films", Applied Physics Letters 84 (2004) 88-90 Hongwei Qu, Wei Yao, T. Garcia, Jiandi Zhang, A.V. Sorokin, S. Ducharme, P.A. Dowben, V.M. Fridkin, "Nanoscale Polarization Manipulation and Conductance Switching in Ultra-Thin Ferroelectric Copolymer Films: P(VDF-TrFE)", Appl. Phys. Lett. 82 (2003) 4322 Bo Xu, Jaewu Choi, A.N. Caruso and P.A. Dowben, "Band Filling and Depletion Through the Doping of Polyaniline Thin Films", Applied Physics Letters 80 (2002) 4342-4344 C.N. Borca, S. Adenwalla, Jaewu Choi, P.T. Sprunger, Stephen Ducharme, Lee Robertson, S. P. Palto, Jianglai Liu, Matt Poulsen, V. M. Fridkin, H. You, P.A. Dowben, "A Lattice Stiffening Transition in Copolymer Films of Vinylidene Fluoride (70%) with Trifluoroethylene (30%)", Phys. Rev. Lett. 83 (1999) 4562-4565 Defect Mediated Coupling in Magnetic Tunnel Junction Structures: P.A. Dowben and B. Doudin, "On the Importance of Defects in Magnetic Tunnel Junctions", Lecture Notes in Physics vol. 678, Springer Verlag (2005) 309-326. Y.A. Ovchenkov, H. Geisler, J.M. Burst, S.N. Thornburg, C.A. Ventrice Jr., Chunjuan Zhang, J. Redepenning, Y. Losovyj, Luis Rosa, P.A. Dowben and B. Doudin, "The Electronic Structure of Metal/Alkane Thiol Self-Assembled Monolayers/Metal Junctions for Magnetoelectronics Applications", Chem. Phys. Lett. 381 (2003) 7-13 L. Bernard, J. Monson, A. Sokolov, Zong-Yuan Liu, C.-S. Yang, P.A. Dowben, B. Doudin, A. Harken, P. Welsch and B.W. Robertson, "Magnetoresistance in Boron Carbide Junctions", Appl. Phys. Lett. 83 (2003) 3743-3745 Ruihua Cheng, A.N. Caruso, L. Yuan, S.-H. Liou, and P.A. Dowben, "Magnetic Coupling in Co/Cr2O3/CrO2 "Trilayer" Films", Applied Physics Letters 82 (2003) 1443-1445 Ya.B. Losovyj, I.N. Yakovkin, S.D. Barrett, Takashi Komesu, and P.A. Dowben, "Evidence of Possible Band Symmetry Effects in STM Studies of Gd Overlayers", Surface Science 520 (2002) 43-52 A. Sokolov, C.-S. Yang, L. Yuan, S.-H. Liou, Ruihua Cheng, H.-K. Jeong, T. Komesu, B. Xu, C.N. Borca, P.A. Dowben and B. Doudin, "Zero-Bias Anomaly in CrO2 Junctions", Europhys. Letters 58 (2002) 448-454 Recent General Papers on the Nometal to Metal Transition: Chun-gang Duan, R.F. Sabiryanov, Jianjun Liu, W.N. Mei, P.A. Dowben and J.R. Hardy, "Strain Induced Half Metal to Semiconductor Transition in GdN", Physical Review Letters 94 (2005) 237201 Ya.B. Losovyj, I.N. Yakovkin, Hae-Kyung Jeong, David Wisbey, and P.A. Dowben, "Lattice-Stiffening Transition in Gadolinium Chains on Furrowed (112) Surfaces", J. Phys. Cond. Matter. 16 (2004) 4711-4724 C. N. Borca, Bo Xu, Takashi Komesu, Hae-Kyung Jeong, M.T. Liu, S.-H. Liou, S. Stadler, Y. Idzerda and P.A. Dowben, "Electronic Structure Modifications Induced by Surface Segregation in La0.65Pb0.35MnO3", Europhysics Letters 56 (2001) 722-728 P.A. Dowben, "The Metallicity of Thin Films and Overlayers", Surface Science Reports 40 (6-8) (2000) 151-247   Graduate Students (and current affiliations): NAME Degree Date Current Affiliation Daniel C. Driscoll Ph.D. 1987 Naval Surface Warfare Center, Virginia Hans-Jorg Ruppender Dipl. Chem. 1987 CEO Dentech, Kaiserslautern, FRG Greg T. Stauf Ph.D. 1988 Advanced Technology Materials Inc., Connecticut Sangramitra Baral M. Sc. 1990 NRL Shikha Varma Ph.D. 1990 Associate Professor of Physics, Institute of Physics, Bhubaneswar, India David LaGraffe Ph.D. 1990 Assistant Professor of Physics at the Air Force Institute of Technology; Lt. Colonel (Army) Yolanda Kime Ph.D. 1991 Associate Professor of Physics, S.U.N.Y-Cortland John Mazurowski M.Sc. 1992 Senior Engineer, Pennsylvania State Univ. Electro-Optic Cntr. http://www.electro-optics.org Yoon-Gi Kim Ph.D. 1992 Samsung Electronics, South Korea Sunwoo Lee Ph.D. 1992 Patent Law, Washington D.C. Dongqi Li Ph.D. 1993 Materials Science Division, Argonne National Labs; on disability leave Jiandi Zhang Ph.D. 1994 Associate Professor of Physics, Florida International University Dongjin Byun Ph.D. 1995 Professor, Dept. of Materials Science and Engineering, Korea University Seong-Don Hwang Ph.D. 1996 Patent Lawyer, Chicago John Kushneir III M.Sc. 1996 Leybold-Inficon, East Syracuse Tara Jean McAvoy M.Sc. 1997 California, Mom Dulip Welipitiya Ph.D. 1997 Hitachi Global Storage, San Jose, CA Carlo Waldfried Ph.D. 1998 Axcelis Jaewu Choi Ph.D. 1998 Associate Prof. of Electrical Engineering, Wayne State University Delia Ristoiu Ph.D. 2000 ST-Microelectronics, Grenoble, France Hanni Dulli Ph.D. 2000 Assist. Prof. of Physics, Oman Medical College, Muscat, Oman Camelia Borca Ph.D. 2001 Staff, Paul Scherrer Institute Laeticia Bernard Diplom Physiker 2002 postdoc at Yale Rui-Hua Cheng Ph.D. 2002 Assistant Professor, Indiana University - Purdue - Indianapolis Takashi Komesu Ph.D. 2002 Staff, Spring 8, Japan Bo Xu Ph.D. 2002 Assistant Professor of Physics, Yanjing University Hae-Kyung Jeong Ph.D. 2003 Research Professor, Sungkyunkwan University Anthony Caruso Ph.D. 2004 Assist. Prof. Univ. of Missouri - Kansas City Luis Rosa Ph.D. 2005 Department of Chemistry, Princeton University Snow Balaz M.Sc. 2005 (Ph.D. in Engineering with J. Brand, 2007) Post-doc., Department of Physics, University of California - Riverside Danqin Feng Ph.D. 2007 Post-doc., Department of Chemistry, University of Chicago Post-doc's (and current affiliations): NAME Date(s) Worked For Dowben Current Affiliation David McIlroy 1993-1996 Prof. of Physics, University of Idaho Jiandi Zhang 1994-1995 Assoc. Prof. of Physics, Florida International University Zhenchen Zhong 1997-1999 JQM Magnetic Systems, China Jaewu Choi 1998-2001 Asoc. Prof., Wayne State University Hae-Kyung Jeong 2003-2004 Research Prof., Sungkyunkwan University Takashi Komesu 2007 Staff, Spring 8, Japan Ihor Ketsman 2006 - present