Current Research

    The research program of Evgeny Tsymbal is focused on the fundamental understanding and the prediction of new functional properties of nanoscale magnetic and ferroelectric materials and structures relevant to device applications such as sensors, memories and storage. First-principles calculations along with model approaches are employed to address a wide range of immensely challenging problems on different levels of complexity. An important ingredient of the research is a strong link to experimental investigations being performed at the University of Nebraska and in other academic and industrial laboratories throughout the world.

Some of the recent research activities include:

· spin-dependent tunnelling and tunnelling magnetoresistance;
· resonant effects in quantum transmission involving interface and defect states;
· spin injection into semiconductors;
· electronic and atomic structure of ferromagnet/organic interfaces;
· interlayer exchange coupling in magnetic layered structures;
· ballistic conductance of magnetic nanocontacts and nanowires;
· domain-wall resistance in constrained geometries;
· ballistic and tunnelling anisotropic magnetoresistance in tunnel and break junctions;
· ferroelectric properties of thin films;
· resistive switching of ferroelectric tunnel junctions;
· magnetoelectric effects at ferromagnet/ferroelectric interfaces.

Evgeny Tsymbal’s research has been funded by National Science Foundation, Nebraska Research Initiative, Seagate Corporation, W. M. Keck Foundation, Office of Naval Research, and Nanoelectronics Research Initiative.

Recent Key Publications

A. Sokolov, C. Zhang, E. Y. Tsymbal, J. Redepenning, and B. Doudin, “Quantized magneto-resistance in atomic-size contacts”, Nature Nanotechnology 2, 171 (2007).

A. N. Chantis, K. D. Belashchenko, E. Y. Tsymbal, and M. van Schilfgaarde, “Tunneling anisotropic magnetoresistance driven by resonant surface states: First-principles calculations of a Fe(001) surface”, Physical Review Letters 98, 046601 (2007).

J. P. Velev, C.-G. Duan, K. D. Belashchenko, S. S. Jaswal, and E. Y. Tsymbal, “Effect of ferroelectricity on electron transport in Pt/BaTiO₃/Pt ferroelectric tunnel junctions”, Physical Review Letters 98, 137201 (2007).

E. Y. Tsymbal and H. Kohlstedt, “Tunneling across a ferroelectric”, Science 313, 181-183 (2006).

E. Y. Tsymbal, “Theory of spin-dependent tunneling: Role of evanescent and resonant states”, in Handbook of Magnetism and Advanced Magnetic Materials, vol. 5, eds. H. Krohnmüller and S. S. P. Parkin (Chichester, UK: John Wiley & Sons Ltd., 2006), p. 2963.

C.-G. Duan, S. S. Jaswal, and E. Y. Tsymbal, “Predicted magnetoelectric effect in Fe/BaTiO₃ multilayers: Ferroelectric control of magnetism”, Physical Review Letters 97, 047201 (2006).

J. D. Burton, R. F. Sabirianov, S. S. Jaswal, E. Y. Tsymbal, and O. N. Mryasov, “Magnetic moment softening and domain wall resistance in Ni nanowires”, Physical Review Letters 97, 077204 (2006).

C.-G. Duan, R. Sabirianov, W.-N. Mei, S. S. Jaswal, and E. Y. Tsymbal, “Interface effect on ferroelectricity at the nanoscale”, Nano Letters 6, 483 (2006).

J. Velev, K. D. Belashchenko, D. Stewart, M. van Schilfgaarde, S. S. Jaswal, and E. Y. Tsymbal, “Negative spin polarization and large tunneling magnetoresistance in epitaxial Co/SrTiO₃/Co magnetic tunnel junctions”, Physical Review Letters 95, 216601 (2005).

M. Y. Zhuravlev, R. F. Sabirianov, S. S. Jaswal, and E. Y. Tsymbal, “Giant electroresistance in ferroelectric tunnel junctions”, Physical Review Letters 94, 246802 (2005).

J. Velev, R. F. Sabirianov, S. S. Jaswal, and E. Y. Tsymbal, “Ballistic anisotropic magnetoresistance”, Physical Review Letters 94, 127203 (2005).

M. Y. Zhuravlev, E. Y. Tsymbal, and A. V. Vedyayev, “Impurity-assisted interlayer exchange coupling across a tunnel barrier”, Physical Review Letters 94, 026806 (2005).

E. Y. Tsymbal, A. Sokolov, I. F. Sabirianov, and B. Doudin, “Resonant inversion of tunneling magnetoresistance”, Physical Review Letters 90, 186602 (2003).

E. Y. Tsymbal and D. G. Pettifor, “Perspectives of Giant Magnetoresistance”, in Solid State Physics, edited by H. Ehrenreich and F. Spaepen, Vol. 56 (Academic Press, 2001) pp.113-237.