Publications

29. Z. Li, R. Parsons, B. Zang, H. Kishimoto, T. Shoji, A. Kato, J. Karel, K. Suzuki, “Dramatic grain refinement and magnetic softening induced by Ni addition in Fe –B based nanocrystalline soft magnetic alloys”, Scripta Materialia 181 82 (2020)

28. J. Karel, D.S. Bouma, J. Martinez, Y. N. Zhang, J. A. Gifford, J. Zhang, G. J. Zhao, D.R. Kim, B. C. Li, Z. Y. Huang, R. Q. Wu, T. Y. Chen, F. Hellman, “Enhanced Spin Polarization of Amorphous FexSi1-xThin Films Revealed by Andreev Reflection Spectroscopy”, Physical Review Materials2 064411 (2018)

27. J. Karel, F. Casoli, L. Nasi, P. Lupo, R. Sahoo, B. Ernst, A. Markou, A. Kalache, R. Cabassi, F. Albertini, C. Felser, “Enhanced Magnetization and Anisotropy in Mn-Ga Thin Films Grown on LSAT”, Applied Physics Letters, 111182405 (2017)

26. C. Wang, A.A. Levin, J. Karel, S. Fabbrici, J. Qian, C.E. Viol Barbosa, S. Ouardi, F. Albertini, W. Schnelle, J. Rohlicek, G.H. Fecher, C. Felser, “Size-dependent structural and magnetic properties of chemically synthesized Co-Ni-Ga nanoparticles”, Nano Research 10 3421 (2017)

25. J. Karel, J.E. Fischer, S. Fabbrici, E. Pippel, P. Werner, M. Vinicius Castergnaro, P. Adler, S. Ouardi, B. Balke, G.H. Fecher, J. Morais, F. Albertini, S.S.P. Parkin, C. Felser, “Influence of Nanoscale Order-Disorder Transitions on the Magnetic Properties of Heusler Compounds for Spintronics”, Journal of Materials Chemistry C, 5 4388 (2017)

24. C. E. ViolBarbosa, J. Karel, J. Kiss, O.D. Gordan, S.G. Altendorf, Y. Utsumi, M.G. Samant, Y.H. Wu, K.-D. Tsuei, C. Felser and S.S.P. Parkin, “A Transparent Conducting Oxide Induced by Liquid Electrolyte Gating”, Proceedings of the National Academy of Sciences, 113 11148 (2016)

23. K. G. Rana, O. Meshcheriakova, J. Kuebler, B. Ernst, J. Karel, R. Hillebrand, E. Pippel, P. Werner, A. Nayak, C. Felser, S.S.P Parkin, “Observation of topological Hall effect in Mn2RhSn films”, New Journal of Physics 18 085007 (2016)

22. J. Karel, F. Casoli, P. Lupo, F. Celegato, P. Tiberto, F. Albertini, C. Felser, “MnxGa1-x Nanodots with High Coercivity and Perpendicular Magnetic Anisotropy”, Applied Surface Science 387 1169 (2016)

21. C. Wang, A.A. Levin, S. Fabbrici, L. Nasi, J. Karel, J. Qian, C.E. Viol Barbosa, S. Ouardi, F. Albertini, W. Schnelle, H. Borrmann, G.H. Fecher, C. Felser, “Tunable Structural and Magnetic Properties of Chemically Synthesized Dual-Phase Co2NiGa Nanoparticles”, Journal of Materials Chemistry C 4 7241 (2016) 

20. J.E. Fischer, J. Karel, S. Fabbrici, P. Adler, S. Ouardi, G.H. Fecher, F. Albertini, C. Felser, “Magnetic properties and Curie temperatures of disordered Heusler compounds: Co1+xFe2-xSi”, Physical Review B 94 024418 (2016)

19. J. Karel, C. Bordel, D.S. Bouma, A. de Lorimier-Farmer, H.J. Lee and F. Hellman, “Scaling of the Anomalous Hall Effect in Lower Conductivity Regimes”, Europhysics Letters 114 57004 (2016)

18. X. Kozina, E. Ikenaga, C.E. ViolBarbosa, S. Ouardi, J. Karel, M. Yamamoto, K. Kobayashi, H.J. Elmers, G. Schönhense, C. Felser, “Development of hard X-ray photoelectron SPLEED-based spectrometer applicable for probing of buried magnetic layer valence states”, Journal of Electron Spectroscopy and Related Phenomena 211, 12 (2016)

17. A.K. Nayak, J. Fischer, Y. Sun, B. Yan, J. Karel, A. Komarek, C. Shekhar, N. Kumar, W. Schnelle, J. Kübler, S.S.P. Parkin, C. Felser, “Non-vanishing Berry curvature driven large anomalous Hall effect in non-collinear antiferromagnet Mn3Ge”, Science Advances 2, e1501870 (2016)

16. J. Karel, F. Casoli, P. Lupo, L. Nasi, S. Fabbrici, L. Righi, F. Albertini, C. Felser, “Evidence for In-Plane Tetragonal c-axis in MnxGa1-x Thin Films using Transmission Electron Microscopy”, Scripta Materialia 114, 165 (2016)

15. D.R. Queen, X. Liu, J. Karel, Q. Wang, R.S. Crandall, T.H. Metcalf and F. Hellman, “Light-induced metastability in pure and hydrogenated amorphous silicon”, Europhysics Letters 112, 26001 (2015)

14. J. Karel, F. Bernardi, C. Wang, A. Beleanu, R. Stinshoff, N.-O. Born, S. Ouardi, U. Burkhardt, G.H. Fecher, C. Felser, “Evidence for Localized Moment Picture in Mn-based Heusler Compounds”, Physical Chemistry Chemical Physics 17, 31707 (2015)

13. C. Wang, A. Levin, L. Nasi, S. Fabbrici, J. Qian, C. Barbosa, S. Ouardi, J. Karel, F. Albertini, H. Bormann; G.H. Fecher, C. Felser, “Chemical Synthesis and Characterization of g-Co2NiGa Nanoparticles with a Very High Curie Temperature”, Chemistry of Materials 27 6994 (2015)

12. D.R. Queen, X. Liu, J. Karel, H.C. Jacks, T.H. Metcalf, F. Hellman, “Two-level Systems in Evaporated Amorphous Silicon”, Journal of Non-Crystalline Solids 426 19 (2015)

11. X. Liu, D.R. Queen, T.H. Metcalf, J.E. Karel, F. Hellman, “Amorphous Dielectric Thin Films with Extremely Low Mechanical Loss”, Archives of Metallurgy and Materials, 60 359 (2015)

10. J. Karel, J. Juraszek, J. Minar, C. Bordel, K.H. Stone, Y.N. Zhang, J. Hu, R.Q. Wu, H. Ebert, J.B. Kortright and F. Hellman, “The Effect of Chemical Order on the Magnetic and Electronic Properties of Epitaxial, Off-Stoichiometry FexSi1-x Thin Films”, Physical Review B 91 144402 (2015)

9. O. Meshcheriakova, A. Koehler, S. Ouardi, T. Kubota, C. Shekhar, J. Karel, C. Barbosa, R. Stinshoff, R. Sahoo, S. Ueda, E. Ikenaga, S. Chadov, S. Mizukami, D. Ebke, G. Fecher, C. Felser, “Structural, electronic, and magnetic properties of perpendicularly magnetised Mn2RhSn thin films” Journal of Physics D: Applied Physics 48 164008 (2015)

8. X. Liu, D. R. Queen, T. H. Metcalf, J. Karel, F. Hellman, “Hydrogen Free Amorphous Silicon with No Tunneling States”, Physical Review Letters, 113, 025503 (2014)

7. J. Karel, C.E. ViolBarbosa, J. Kiss, J. Jeong, N. Aetukuri, M.G. Samant, X. Kozina, E. Ikenaga, G.H. Fecher, C. Felser and S. S. P. Parkin, “Distinct Electronic Structure of the Electrolyte-Gate Induced Conducting Phase in Vanadium Dioxide Revealed by High Energy Photoelectron Spectroscopy”, ACS Nano, 8, 5474 (2014)

6. J. Karel, Y.N. Zhang, C. Bordel, K.H. Stone, C.A. Jenkins, David J. Smith, J. Hu, R. Q. Wu, S.M. Heald, J.B. Kortright and F. Hellman, “Using Structural Disorder to Enhance the Magnetism and Spin Polarization in FexSi1-x Thin Films for Spintronics”, Materials Research Express 1 026102 (2014)

5. X. Kozina, J. Karel, S. Ouardi, S. Chadov, G. H. Fecher, C. Felser, G. Stryganyuk, B. Balke, T. Ishikawa, T. Uemura, M. Yamamoto, E. Ikenaga, S. Ueda, and K. Kobayashi, “Probing the electronic states of high-TMR off-stoichiometric Co2MnSi thin films by hard x-ray photoelectron spectroscopy”, Physical Review B 89, 125116 (2014)

4. D.R. Queen, X. Liu, J. Karel, T.H. Metcalf and F. Hellman, “Excess Specific Heat in Evaporated Amorphous Si”, Physical Review Letters 110, 135901 (2013)

3. H.-J. Lee, C. Bordel, J. Karel, David W. Cooke, M. Charilaou and F. Hellman, “Electron-mediated Ferromagnetic Behavior in CoO/ZnO Multilayers”, Physical Review Letters 110, 087206 (2013)

2. A. X. Gray, J. Karel, J. Minár, C. Bordel, H. Ebert, J. Braun, S. Ueda, Y. Yamashita, Lu Ouyang, David J. Smith, K. Kobayashi, F. Hellman, and C. S. Fadley, “Hard X-ray Photoemission Study of Near-Heusler FexSi1-x Alloys”, Physical Review B, 83, 195112 (2011)

1. Li Zeng, J. X. Cao, E. Helgren, J. Karel, E. Arenholz, Lu Ouyang, David J. Smith, R. Q. Wu and F. Hellman, “Distinct local structure and magnetism for Mn in amorphous Si and Ge”, Physical Review B, 82, 165202 (2010)

%d bloggers like this: