Recent publications

Regular papers

  • Szaller, Dávid; Bordács, Sándor; Kocsis, Vilmos; Rõõm, Toomas; Nagel, Urmas; Kézsmárki, István (2014). Effect of spin excitations with simultaneous magnetic- and electric-dipole character on the static magnetoelectric properties of multiferroic materials.Physical Review B, 89, 184419. See preprint arXiv:1401.3306 [cond-mat.mtrl-sci].
  • Kézsmárki, I.; Szaller, D.; Bordács, S. ;Kocsis, V.;Tokunaga, Y.; Taguchi, Y.; Murakawa, H.; Tokura, Y. ; Engelkamp, H.; Rõõm, T.; Nagel, U. (2014). One-way transparency of four-coloured spin-wave excitations in multiferroic materials. Nature Communications, 5, 3203. See preprint at arXiv:1310.0789 [cond-mat.mtrl-sci] and news article at FYSSIKA.EE (in Estonian)
  • Rõõm, T.; Peedu, L.; Ge, Min; Hüvonen, D.; Nagel, U.; Ye, Shufeng; Xu, Minzhong; Bacic, Z; Mamone, S.; Levitt, M.H.; Caravetta, M.; Chen, J.Y.-H.; Lei, Xuengong; Turro, N.J.; Murata, Y.; Komatsu, K. (2013). Infrared spectroscopy of small-molecule fullerenes. PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, 371(1998), 20110631
  • Nagel, U.; Fishman, Randy S.; Katuwal, T.; Engelkamp, H.; Talbayev, D.; Yi, Hee Taek; Cheong, S.-W.; Rõõm, T. (2013). Terahertz Spectroscopy of Spin Waves in Multiferroic BiFeO3 in High Magnetic Fields. Physical Review Letters, 110, 257201 – [5 pages].Published online: 17 June 2013. Preprint arXiv:1302.2491 [cond-mat.str-el] and news article at FYYSIKA.EE (in Estonian).
  • Bordacs, Sandor; Kezsmarki, Istvan; Szaller, David; Demko, Laszlo; Kida, Noriaki; Murakawa, Hiroshi; Onose, Yoshinori; Shimano, Ryo; Rõõm, Toomas; Nagel, Urmas; Miyahara, Shin; Furukawa, Nobuo; Tokura, Yoshinori. Chirality of Matter Shows Up via Spin Excitations. Nature Physics, Published online: 26 August 2012 | doi:10.1038/nphys2387 and news article at FYYSIKA.EE (in Estonian).
  • C. Beduz, M. Carravetta, J. Chen, M. Concistre, M. Denning, M. Frunzi, A. Horsewill, O. Johannessen, R. Lawler, X. Lei, M. Levitt, Y. Li, S. Mamone, Y. Murata, U. Nagel, T. Nishida, J. Ollivier, S. Rols, T. Room, R. Sarkar, N. Turro, and Y. Yang, “Quantum rotation ofortho and para-water encapsulated in a fullerene cage”, Proc. Natl. Acad. Sci., 109, 12894-12898 (2012).
  • Hall, J.S.; Nagel, U.; Uleksin, T.; Rõõm, T; Williams, T.; Luke, G.; Timusk, T. Observation of multiple-gap structure in hidden order state of URu2Si2 from optical conductivity. Phys. Rev. B 86, 035132 (2012).
  • K. Penc, J. Romhányi, T. Rõõm, U. Nagel, Á. Antal, T. Fehér, A. Jánossy, H. Engelkamp, H. Murakawa, Y. Tokura, D. Szaller, S. Bordács, and I. Kézsmárki. Spin-Stretching Modes in Anisotropic Magnets: Spin-Wave Excitations in the Multiferroic Ba2CoGe2O7.Phys. Rev. Lett. 108, 257203 (2012).
  • Nagel, U.; Uleksin, T.; Rõõm, T.; Lobo, R.P.S.M.; Lejay, P.; Homes, C.C.; Hall, J.; Kinross, A.W.; Purdy, S.; Williams, T. J.; Luke, G.M.; Timusk, T. (2012). The normal state of URu2Si2: spectroscopic evidence for an anomalous Fermi liquid. Proceedings of the National Academy of Sciences of the United States of America, 109, 19161
  • Min Ge, U. Nagel, D. Hüvonen, T. Rõõm, S. Mamone, M. H. Levitt, M. Carravetta, Y. Murata, K. Komatsu, J. Y.-C. Chen, and N. J. Turro. Interaction potential and infrared absorption of endohedral H2 in C60. J. Chem. Phys. 134, 054507 (2011).
  • R.P.S.M. Lobo, Y. M. Dai, U. Nagel, T. Rõõm, J. P. Carbotte, T. Timusk, A. Forget, and D. Colson. Optical signature of subgap absorption in the superconducting state of Ba(Fe1−xCox)2As2. Phys. Rev. B 82, 100506(R) (2010).
  • D. Hüvonen, U. Nagel, T. Rõõm, Y. J. Choi, C. L. Zhang, S. Park,  S.-W. Cheong. Magnetic excitations and optical transitions in the multiferroic spin-1/2 system LiCu2O2. Phys. Rev. B, 80, 100402(R) (2009); preprint from arXiv:0904.2329v2 [cond-mat.str-el]
  • S. Mamone, Min Ge, D. Hüvonen, U. Nagel, A. Danquigny, F. Cuda, M. C. Grossel, Y. Murata, K. Komatsu, M. H. Levitt, T. Rõõm, M. Carravetta. Rotor in a Cage: Infrared Spectroscopy of an Endohedral Hydrogen-Fullerene Complex. J. Chem. Phys., 130, 081103 (2009); preprint from arXiv:0807.1589 [physics.chem-ph]
  • J. Yang, D. Huvonen, U. Nagel, T. Room, N. Ni, P. C. Canfield, S. L. Budko, J.P. Carbotte, T. Timusk. Optical spectroscopy of superconducting Ba0.55K0.45Fe2As2: evidence for strong coupling to low energy bosons. Physical Review Letters, 102, 187003 (2009); preprint from arXiv:0807.1040v1 [cond-mat.supr-con]
  • C. C. Homes,1,2 S. V. Dordevic, A. Gozar, G. Blumberg, T. Rõõm, D. Hüvonen, U. Nagel, A. D. LaForge, D. N. Basov, and H. Kageyama. Infrared spectra of the low-dimensional quantum magnet SrCu2(BO3)2: Measurements and ab initio calculations. Phys. Rev. B 79, 125101 (2009).
  • Terahertz Spectroscopy of Low-Dimesional Spin Systems. PhD thesis of Dan Hüvonen. Tallinn, 2008.
  • U. Nagel, D. Hüvonen, E. Joon, J. S. Kim, R.K. Kremer, and T. Rõõm; Far-infrared signature of the superconducting gap in intercalated graphite CaC6. Physical Review B, 78, 041404(R) (2008); preprint from arXiv:0804.2606v2 [cond-mat.supr-con]
  • Hüvonen, Dan; Nagel, Urmas; Rõõm, Toomas; Haas, P.; Dressel, M.; Hwang, J.; Timusk, T.; Wang, Y.-J.; Akimitsu, J. Magneto-optic far-infrared study of Sr14Cu24O41: Triplet excitations in chains. Physical Review B, 76(13), 134418 (2007); preprint fromarXiv:0706.4213v1 [cond-mat.other]
  • T. Rőőm, D. Hüvonen, U. Nagel, J. Hwang, T. Timusk, H. Kageyama. Far-infrared spectroscopy of spin excitations and Dzyaloshinskii-Moriya interactions in a Shastry-Sutherland compund SrCu2(BO3)2.Phys. Rev. B, vol 70, pp. 144417-8 (2004); preprint fromarXiv:cond-mat/0405434v3 [cond-mat.other]
  • T. Rőőm, D. Hüvonen, U. Nagel, Y.-J. Wang, R.K. Kremer. Low-energy excitations and dynamic Dzyaloshinskii-Moriya interaction in α’-NaV2O5 studied by far-infrared spectroscopy. – Phys. Rev. B vol. 69, pp. 144410-19 (2004); preprint from arXiv:cond-mat/0402419v2 [cond-mat.str-el]
  • Rőőm T., Nagel U., Lippmaa E., Kageyama H., Onizuka K., Ueda Y. Far-infrared study of the two-dimensional dimer spin system SrCu2(BO3)2 . Phys. Rev. B, vol 61, 14342-14345 (2000); preprint from arXiv:cond-mat/9909284v3 [cond-mat.str-el]

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