Department of Physics and Astronomy
156 Behlen Laboratory
Phone: (402) 472-0180
Email: rskomski2@unl.edu
The research of Ralph Skomski focuses on theory of magnetic nanostructures. The main aim is to model the behavior of nanostructures and to make predictions about conceivable but difficult-to-produce materials. The relevant length scales of the involved structural features vary from a few interatomic distances to more than 100 nm, and each length scale has its own characteristics. Examples of small-scale magnetic nanostructures of interest are nanotubes, nanorings, patterned thin films, and particulate materials. These structures exhibit, among other features, interesting spin-wave and magnetization-reversal modes. On an atomic scale, chemical substitutions, interstitial modification, and changes in the crystal structure are exploited to tailor intrinsic properties such as anisotropy, Curie temperature and magnetic moment. On length scales larger than a few nm, the magnetic material can be treated as a continuum. In this regime, the atomic properties enter the consideration as micromagnetic parameters. The morphological peculiarities of magnetic nanostructures lead to a variety of novel micromagnetic effects. One example is intergranular exchange coupling, which has a strong effect on the performance of advanced permanent magnets, magnetic recording media, and magnetoresistive materials.
Other research areas of interest are time-dependent magnetization processes (magnetic viscosity and fast processes), the spin structure of half-metallic ferromagnets as well as topics such as RKKY interactions between nanomagnets embedded in a nonmagnetic metallic matrix. Emphasis is on analytic models, which are designed to complement and guide other scientists' numerical approaches, such as band-structure calculations.
2012
Berry phase from a randomly fluctuating magnetic field, Ralph Skomski
2011
Magnetic entropy changes in nanogranular Fe:Ni61Cu39, Steven A. Michalski, Ralph A. Skomski, Tathagata Mukherjee, Xingzhong Li, Christian Binek, and David J. Sellmyer
2010
Interstitial-nitrogen effect on phase transition and magnetocaloric effect in Mn(As,Si) (invited), W. B. Cui, X. K. Lv, F. Yang, Ralph Skomski, Y. Yu, X. G. Zhao, W. Liu, and Z.D. Zhang
Magnetic surface nanostructures, Axel Enders, Ralph A. Skomski, and J. Honolka
Permittivity and permeability of Fe(Tb) nanoparticles and their microwave absorption in the 2–18 GHz range, Z. Han, D. Li, M. Tong, X. Wei, Ralph Skomski, W. Liu, Z. D. Zhang, and David J. Sellmyer
Structural, magnetic and magneto-transport properties of Pt-alloyed MnBi thin films, Parashu Kharel, Ralph Skomski, Roger D. Kirby, and David J. Sellmyer
Magnetic antiphase domains in Co/Ru/Co trilayers, Zhen Li; Ralph Skomski; Steven Michalski; Lanping Yue,2 and Roger D. Kirbyng; and Roger D. Kirby
Entropy localization in magnetic compounds and thin-film nanostructures, Ralph Skomski, Christian Binek, S. Michalski, T. Mukherjee, Axel Enders, and David J. Sellmyer
Magnetic anisotropy in itinerant magnets, Ralph Skomski, A. Kashyap, A. Solanki, Axel Enders, and David J. Sellmyer
Permanent magnetism of dense-packed nanostructures, Ralph Skomski, Yi Liu, Jeffrey Shield, G. C. Hadjipanayis, and David J. Sellmyer
Magnetism of core-shell Ti:TiO nanoparticles, Xiaohui Wei, Ralph Skomski, Balamurugan Balasubramanian, and David J. Sellmyer
2009
Magnetic Correlations in Nanocomposite FePt:Au and FePt:C Films, Thomas A. George, Ralph Skomski, and David J. Sellmyer
Magnetism of FePt Surface Alloys, J. Honolka, T. Y. Lee, K. Kuhnke, Axel Enders, Ralph Skomski, S. Bornemann, S. Mankovsky, J. Minar, J. Staunton, H. Ebert, M. Hessler, K. Fauth, G. Schutz, A. Buchsbaum, M. Schmid, P. Varga, and K. Kern
Graded Permanent Magnets, Ralph Skomski, J. Hadjipanayis, and David J. Sellmyer
Dzyaloshinski–Moriya Micromagnetics of Magnetic Surface Alloys, Ralph Skomski, J. Honolka, S. Bornermann, H. Ebert, and Axel Enders
Magnetism of TiO and TiO2 Nanoclusters, Xiaohui Wei, Ralph Skomski, Balamurugan Balasubramanian, Z. G. Sun, Stephen Ducharme, and David J. Sellmyer
2008
The local environment of Co in B5CHx, Peter Dowben, A. Yu. Ignatov, Jing Lui, and Ralph Skomski
Nanostructure and magnetic properties of L10 FePt:X films, Thomas A. George, Zhen Li, Minglang Yan, Yingfan Xu, Ralph Skomski, and David Sellmyer
Temperature dependence of half-metallic hybridization gaps, Ralph Skomski
Temperature- and field-induced entropy changes in nanomagnets, Ralph Skomski, Christian Binek, T. Mukherjee, Sarbeswar Sahoo, and David J. Sellmyer
Nucleation and wall motion in graded media, Ralph Skomski, Thomas A. George, and David J. Sellmyer
Hysteresis of ultrasmall Fe–Pt particles, Ralph Skomski, J. P. Liu, C. B. Rong, and David J. Sellmyer
Band-structure and correlation effects in the Co(111) planes of CoO, Ralph Skomski, Xiaohui Wei, and David J. Sellmyer
Substrate-controlled growth and magnetism of nanosize Fe clusters on Pt, Ralph Skomski, J. Zhang, V. Sessi, J. Honolka, K. Kern, and Axel Enders
Proteresis in Co:CoO core-shell nanoclusters, X.-H. Wei, Ralph Skomski, Zhiguang Sun, and David Sellmyer
Ordered Layers of Co Clusters on BN Template Layers, J. Zhang, V. Sessi, C. H. MIchaelis, I. Brihuega, J. Honolka, K. Kern, Ralph Skomski, X. Chen, G. Rojas, and Axel Enders
2007
Coupled precession modes in indirect exchange-coupled [Pt/Co]–Co thin films, Steven Michalski, Jian Zhou, Ralph Skomski, and Roger D. Kirby
Surface anisotropy and magnetic freezing of MnO nanoparticles, Marco Morales Torres, Ralph Skomski, Shannon Fritz, G. Shelburne, Jeffrey E. Shield, Ming Yin, Stephen O'Brien, and Diandra Leslie-Pelecky
Structural phase transition and ferromagnetism in monodisperse 3 nm FePt particles, Chuan-bing Rong, Narayan Poudyal, Girija S. Chaubey, Vikas Nandwana, Ralph Skomski, Y. Q. Wu, M. J. Kramer, and J. Ping Liu
Finite-temperature depolarization in half metals, Ralph Skomski
Phase formation in L1 0 magnets, Ralph Skomski
Role of thermodynamic fluctuations in magnetic recording (invited), Ralph Skomski
Effective Demagnetizing Factors of Complicated Particle Mixtures, Ralph Skomski, G. C. Hadjipanayis, and David J. Sellmyer
Magnetic impurities in magic-number clusters, Ralph Skomski and David J. Sellmyer
Magnetization Reversal in Cubic Nanoparticles With Uniaxial Surface Anisotropy, Ralph Skomski, Xiao-Hui Wei, and David J. Sellmyer
Continuous/Cluster-Pinned Recording Media, Ralph Skomski, M. L. Yan, Yinfan Xu, and David J. Sellmyer
Temperature-dependent orbital-moment anisotropy in dilute magnetic oxides, Jun Zhang, Ralph Skomski, Yongfeng Lu, and David J. Sellmyer
Structure and magnetism of V-doped SnO2 thin films: effect of the substrate, Jun Zhang, Ralph Skomski, L. P. Yue, Yongfeng Lu, and David J. Sellmyer
2006
"Introduction" to Advanced Magnetic Nanostructures, David J. Sellmyer and Ralph Skomski
Magnetic Materials (Appendix to Advanced Magnetic Nanostructures [2006]), David J. Sellmyer and Ralph Skomski
"Preface" to Advanced Magnetic Nanostructures, David J. Sellmyer and Ralph Skomski
Assembly of high-anisotropy L10 FePt nanocomposite films, David J. Sellmyer, Yinfan Xu, M. L. Yan, Yucheng Sui, Jian Zhou, and Ralph Skomski
Magnetic reversal in three-dimensional exchange-spring permanent magnets, Jeffrey E. Shield, J. Zhou, S. Aich, V.K. Ravindran, Ralph Skomski, and David J. Sellmyer
Finite-temperature anisotropy of magnetic alloys, Ralph Skomski, O.N. Mryasov, J. Zhou, and David J. Sellmyer
Nanomagnetic Models, Ralph Skomski and Jian Zhou
Magnetic Aging, Ralph Skomski, Jian Zhou, Roger D. Kirby, and David J. Sellmyer
Micromagnetic energy barriers, Ralph Skomski, Jian Zhou, Roger D. Kirby, and David J. Sellmyer
Indirect exchange in dilute magnetic semiconductors, Ralph Skomski, J. Zhou, Jun Zhang, and David J. Sellmyer
Fast and Slow Magnetization Processes in Magnetic Recording Media, Jian Zhou, Ralph Skomski, Steven A. Michalski, Roger D. Kirby, and David J. Sellmyer
Structural effects on exchange in nanocluster perpendicular recording media, J. Zhou, Ralph Skomski, and David J. Sellmyer
2005
Enhanced coercivity in thermally processed (Nd,Dy)(Fe,Co,Nb,B) 5.5/ α-Fe nanoscale multilayer magnets, W. Liu, X.Z. Li, J.P. Liu, X.K. Sun, C.L. Chen, Ralph Skomski, Z.D. Zhang, and David J. Sellmyer
Phase transformations and thermodynamic properties of nanocrystalline FePt powders , J. Lyubina, O. Gutfleisch, Ralph Skomski, K.-H. Müller, and L. Schultz
Nanomagnetic Structures: Fabrication and Interactions, David J. Sellmyer, Y. C. Sui, Yinfan Xu, M. L. Yan, K. D. Sorge, and Ralph Skomski
High-Anisotropy Nanocluster Films for High-Density Perpendicular Recording, David J. Sellmyer, Minglang Yan, Yinfan Xu, and Ralph Skomski
Intra-atomic aspects of magnon-plasmon interactions, Ralph Skomski and Peter A. Dowben
Atomic and micromagnetic aspects of L10 magnetism, Ralph Skomski, Arti Kashyap, and Jian Zhou
Anisotropic exchange, Ralph Skomski, A. Kashyap, Jian Zhou, and David J. Sellmyer
Magnetic materials for finite-temperature quantum computing, Ralph Skomski, J. Zhou, A.Y. Istomin, Anthony F. Starace, and David J. Sellmyer
Relaxation in magnetic nanostructures, Ralph Skomski, J. Zhou, and David J. Sellmyer
Geometry and magnetism of L10 nanostructures, Kory D. Sorge, Ralph Skomski, Maria Daniil, Steven Michalski, L. Gao, Jian Zhou, M. Yan, Yucheng Sui, Roger D. Kirby, Sy_Hwang Liou, and David J. Sellmyer
Template-mediated assembly of FePt L10 clusters under external magnetic field, Yucheng Sui, W. Liu, L.P. Yue, X.Z. Li, J. Zhou, Ralph Skomski, and David J. Sellmyer
Magnetic properties and L10 phase formation of FePt films prepared by high current-density ion-beam irradiation and rapid thermal annealing methods, T. Yokota, M.L. Yan, Yinfan Xu, L. Gao, R. Zhang, LeighAnn Nicholl, Lu Yuan, Ralph Skomski, David J. Sellmyer, Sy_Hwang Liou, Chih-Huang Lai, Cheng-Han Yang, and Sheng-Huang Huang
Sample preparation and annealing effects on the ferromagnetism in Mn-doped ZnO, Jun Zhang, Ralph Skomski, and David J. Sellmyer
Highly coercive thin-film nanostructures, Jian Zhou, Ralph Skomski, Arti Kashyap, Kory D. Sorge, Yucheng Sui, Maria Daniil, L. Gao, M. L. Yan, Sy_Hwang Liou, Roger D. Kirby, and David J. Sellmyer
Magnetization reversal in particulate L10 nanostructures, Jian Zhou, Ralph Skomski, Kory D. Sorge, and David J. Sellmyer
Rapidly annealed exchange-coupled Sm-Co/Co multilayers, J. Zhou, Ralph Skomski, Yi Liu, Yucheng Sui, W. Liu, and David J. Sellmyer
2004
Field-controlled domain-wall resistance in magnetic nanojunctions, J. D. Burton, A. Kashyap, Mikhail Ye. Zhuravlev, Ralph Skomski, Evgeny Y. Tsymbal, Sitaram Jaswal, O.N. Mryasov, and R.W. Chantrell
Are half-metallic ferromagnets half metals? (invited), Peter A. Dowben and Ralph Skomski
Focused Ion Beam Milled CoPt Magnetic Force Microscopy Tips for High Resolution Domain Images, L. Gao, L. P. Yue, T. Yokota, Ralph Skomski, Sy-Hwang Liou, H. Takahoshi, H. Saito, and S. Ishio
Magnetism of L10 compounds with the composition MT (M = Rh, Pd, Pt, Ir and T = Mn, Fe, Co, Ni), A. Kashyap, Ralph Skomski, Ashok K. Solanki, Yinfan Xu, and David J. Sellmyer
First principles study of transition-metal substitutions in Sm–Co permanent magnets, R.F. Sabirianov, A. Kashyap, Ralph Skomski, Sitaram Jaswal, and David J. Sellmyer
Quantum entanglement of anisotropic magnetic nanodots, Ralph Skomski, Andrei Y. Istomin, Anthony F. Starace, and David J. Sellmyer
Quantum entanglement of anisotropic magnetic nanodots, Ralph Skomski, Andrei Y. Istomin, Anthony F. Starace, and David J. Sellmyer
Multidomain and incoherent effects in magnetic nanodots, Ralph Skomski, A. Kashyap, Kory D. Sorge, and David J. Sellmyer
Noncollinear spin states and competing interactions in half-metals, Ralph Skomski, Jian Zhou, Peter A. Dowben, and David J. Sellmyer
Domain-Wall Pinning at Inhomogenities of Arbitrary Cross-Sectional Geometry, Ralph Skomski, Jian Zhou, Arti Kashyap, and David J. Sellmyer
Interactions and switching behavior of anisotropic magnetic dots, Kory D. Sorge, A. Kashyap, Ralph Skomski, Lanping Yue, L. Gao, Roger D. Kirby, Sy_Hwang Liou, and David J. Sellmyer
Magnetic nanotubes produced by hydrogen reduction, Yucheng Sui, Ralph Skomski, Kory D. Sorge, and David J. Sellmyer
Nanotube magnetism, Yucheng Sui, Ralph Skomski, Kory D. Sorge, and David J. Sellmyer
Growth and magnetism of FePt:C composites in nanoscale channels, Yucheng Sui, J. Zhou, X.Z. Li, Ralph Skomski, and David J. Sellmyer
Hysteresis of Granular FePt:Ag Films With Perpendicular Anisotropy, M. L. Yan, Ralph Skomski, A. Kashyap, L. Gao, Sy-Hwang Liou, and David J. Sellmyer
Magnetization Reversal and Giant Coercivity in Sm-Co/Cu-Ti Particulate Films, Jian Zhou, Arti Kashyap, Yi Liu, Ralph Skomski, and David J. Sellmyer
2003
Finite-temperature spin polarization in half-metallic ferromagnets, Peter A. Dowben and Ralph Skomski
Exchange Interactions and Curie Temperature of Y–Co Compounds, Arti Kashyap, Ralph Skomski, Renat F. Sabiryanov, Sitaram Jaswal, and David J. Sellmyer
Spin-wave modes in magnetic nanowires, Ralph Skomski, M. Chipara, and David J. Sellmyer
Exchange through nonmagnetic insulating matrix, Ralph Skomski, A. Kashyap, Y. Quiang, and David J. Sellmyer
Finite-Temperature Anisotropy of PtCo Magnets, Ralph Skomski, Arti Kashyap, and David J. Sellmyer
Equivalence of sweep-rate and magnetic-viscosity dynamics, Ralph Skomski, Roger D. Kirby, and David J. Sellmyer
Spin structure at nanojunctions and constrictions, Ralph Skomski and David J. Sellmyer
CoPt hard magnetic nanoparticle films synthesized by high temperature chemical reduction , Yucheng Sui, L. Yue, Ralph Skomski, X.Z. Li, J. Zhou, and David J. Sellmyer
Magnetic transitions in disordered GdAl2, D. S. Williams, Paul M. Shand, Thomas M. Pekarek, Ralph Skomski, Valeri G. Petkov, and Diandra Leslie-Pelecky
Magnetic hysteresis of mechanically alloyed Sm–Co nanocrystalline powders, J. Zhou, Ralph Skomski, and David J. Sellmyer
2002
Magnetic force microscopy observations of the magnetic behavior in Co–C nanodot arrays, L. Gao, Sy_Hwang Liou, M. Zheng, Ralph Skomski, M. L. Yan, David J. Sellmyer, and N.I. Polushkin
Magnetic force microscopy observations of the magnetic behavior in Co–C nanodot arrays, L. Gao, Sy_Hwang Liou, M. Zheng, Ralph Skomski, M.L. Yan, David J. Sellmyer, and N.I. Polushkin
Exact nucleation modes in arrays of magnetic particles, Ralph Skomski
Exchange-controlled magnetic anisotropy, Ralph Skomski
The finite-temperature densities of states for half-metallic ferromagnets, Ralph Skomski and Peter A. Dowben
Structure and magnetic properties of ferromagnetic nanowires in self-assembled arrays, H. Zeng, Ralph Skomski, L. Menon, Yi Liu, S. Bandyopadhyay, and David J. Sellmyer
Permanent-Magnet Properties of Thermally Processed FePt and FePt–Fe Multilayer Films, Jian Zhou, Ralph Skomski, Xingzhong Li, Wei Tang, George C. Hadjipanayis, and David J. Sellmyer
2001
High-temperature magnetic properties of mechanically alloyed SmCo 5 and YCo5 magnets, I.A. Al-Omari, Ralph Skomski, R.A. Thomas, D. Leslie-Pelecky, and David J. Sellmyer