Publication

Original Paper

1. “Multi-step topological transitions among meron and skyrmion crystals in a centrosymmetric magnet”
   H. Yoshimochi, R. Takagi, J. Ju, N. D. Khanh, H. Saito, H. Sagayama, H. Nakao, S. Itoh, Y. Tokura, T. Arima, S. Hayami, T. Nakajima, S. Seki
   Nature Physics (2024). [Advanced online publication]




2. “Task-adaptive physical reservoir computing”
   O. Lee, T. Wei, K. D Stenning, J. C. Gartside, D. Prestwood, S. Seki, A. Aqeel, K. Karube, N. Kanazawa, Y. Taguchi, C. Back, Y. Tokura, W. R. Branford, H. Kurebayashi
   Nature Materials 23, 79 (2024).




3. “Spontaneous topological Hall effect induced by non-coplanar antiferromagnetic order in intercalated van der Waals materials”
   H. Takagi, R. Takagi, S. Minami, T. Nomoto, K. Ohishi, M.-T. Suzuki, Y. Yanagi, M. Hirayama, N. D. Khanh, K. Karube, H. Saito, D. Hashizume, R. Kiyanagi, Y. Tokura, R. Arita, T. Nakajima, S. Seki
   Nature Physics 19, 961 (2023).




4. “Nonreciprocal Phonon Propagation in a Metallic Chiral Magnet”
   T. Nomura, X.-X. Zhang, R. Takagi, K. Karube, A. Kikkawa, Y. Taguchi, Y. Tokura, S. Zherlitsyn, Y. Kohama, S. Seki
   Phys. Rev. Lett. 130, 176301 (2023).




5. “Quantum oscillations in the centrosymmetric skyrmion-hosting magnet GdRu₂Si₂“
   N. Matsuyama, T. Nomura, S. Imajo, T. Nomoto, R. Arita, K. Sudo, M. Kimata, N. D. Khanh, R. Takagi, Y. Tokura, S. Seki, K. Kindo, Y. Kohama
   Phys. Rev. B 107, 104421 (2023). [Editor's Suggestion]




6. “Rhombic skyrmion lattice coupled with orthorhombic structural distortion in EuAl₄“
   M. Gen, R. Takagi, Y. Watanabe, S. Kitou, H. Sagayama, N. Matsuyama, Y. Kohama, A. Ikeda, Y. Onuki, T. Kurumaji, T. Arima, S. Seki
   Phys. Rev. B 107, L020410 (2023).




7. “Pattern recognition with neuromorphic computing using magnetic field-induced dynamics of skyrmions”
   T. Yokouchi, S. Sugimoto, B. Rana, S. Seki, N. Ogawa, Y. Shiomi, S Kasai, Y. Otani
   Science Advances 8, 5652 (2022).




8. “Higher-order modulations in the skyrmion lattice phase of Cu₂OSeO₃“
   J. D. Reim, S. Matsuzaka, K. Makino, S. Aji, R. Murasaki, D. Higashi, D. Okuyama, Y. Nambu, E. P. Gilbert, N. Booth, S. Seki, Y. Tokura, T. J. Sato
   Phys. Rev. B 106, 104406 (2022).




9. “Square and rhombic lattices of magnetic skyrmions in a centrosymmetric binary compound”
   R. Takagi, N. Matsuyama, V. Ukleev, L. Yu, J. S. White, S. Francoual, J. R. L. Mardegan, S. Hayami, H. Saito, K. Kaneko, K. Ohishi, Y. Onuki, T. Arima, Y. Tokura, T. Nakajima, S. Seki
   Nature Communications 13, 1472 (2022).




10. “Direct visualization of the three-dimensional shape of skyrmion strings in a noncentrosymmetric magnet”
    S. Seki, M. Suzuki, M. Ishibashi, R. Takagi, N. D. Khanh, Y. Shiota, K. Shibata, W. Koshibae, Y. Tokura, T. Ono
    Nature Materials 21, 181 (2022).




11. “Zoology of multiple-Q spin textures in a centrosymmetric tetragonal magnet with itinerant electrons”
    N. D. Khanh, T. Nakajima, S. Hayami, S. Gao, Y. Yamasaki, H. Sagayama, H. Nakao, R. Takagi, Y. Motome, Y. Tokura, T. Arima, S. Seki
    Advanced Science 2105452 (2022).




12. “Enhanced gyrotropic birefringence and natural optical activity on electromagnon resonance in a helimagnet”
    S. Iguchi, R. Masuda, S. Seki, Y. Tokura, Y. Takahashi
    Nature Communications 12, 6674 (2021).




13. “Tunable gigahertz dynamics of low-temperature skyrmion lattice in a chiral magnet”
    O. Lee, J. Sahliger, A. Aqeel, S. Khan, S. Seki, H. Kurebayashi, C. H. Back
    J. Phys.: Condens. Matter 34, 095801 (2021).




14. “Hybridized magnon modes in the quenched skyrmion crystal”
    R. Takagi, M. Garst, J. Sahliger, C. H. Back, Y. Tokura, S. Seki
    Phys. Rev. B 104, 144410 (2021).




15. “Coupling microwave photons to topological spin textures in Cu₂OSeO₃“
    S. Khan, O. Lee, T. Dion, C. W. Zollitsch, S. Seki, Y. Tokura, J. D. Breeze, and H. Kurebayashi
    Phys. Rev. B 104, L100402 (2021).




16. “Real-space observations of 60-nm skyrmion dynamics in an insulating magnet under low heat flow”
    X. Z. Yu, F. Kagawa, S. Seki, M. Kubota, J. Masell, F. S. Yasin, K. Nakajima, M. Nakamura, M. Kawasaki, N. Nagaosa, Y. Tokura
    Nature Communications 12, 5079 (2021).




17. “Topological defect-mediated skyrmion annihilation in three dimensions”
    M. T. Birch, D. Cortés-Ortuño, N. D. Khanh, S. Seki, A. Štefančič, G. Balakrishnan, Y. Tokura, P. D. Hatton
    Communications Physics 4, 175 (2021).




18. “Nonreciprocity of spin waves in the conical helix state”
    N. Ogawa, L. Köhler, M. Garst, S. Toyoda, S. Seki, Y. Tokura
    PNAS 118, 2022927118 (2021).




19. “Imaging the coupling between itinerant electrons and localised moments in the centrosymmetric skyrmion magnet GdRu₂Si₂“
    Y. Yasui, C. Butler, N. D. Khanh, S. Hayami, T. Nomoto, T. Hanaguri, Y. Motome, R. Arita, T. Arima, Y. Tokura, S. Seki
    Nature Communications 11, 5925 (2020).




20. “Particle-size dependent structural transformation of skyrmion lattice”
    R. Takagi, Y. Yamasaki, T. Yokouchi, V. Ukleev, Y. Yokoyama, H. Nakao, T. Arima, Y. Tokura, S. Seki
    Nature Communications 11, 5685 (2020).




21. “Structural analysis of high-pressure phase for skyrmion-hosting multiferroic Cu₂OSeO₃“
    E. Nishibori, S. Karatsu, C. Terakura, N. Takeshita, M. Kinoshita, S. Ishiwata, Y. Tokura, S. Seki
    Phys. Rev. B 102, 201106(R) (2020). (arXiv:2009.07577)




22. “Bloch Lines Constituting Antiskyrmions Captured via Differential Phase Contrast”
    F. S. Yasin, L. Peng, R. Takagi, N. Kanazawa, S. Seki, Y. Tokura, X. Z. Yu
    Advanced Materials 32, 2004206 (2020).




23. “Nanometric square skyrmion lattice in a centrosymmetric tetragonal magnet”
    N. D. Khanh, T. Nakajima, X. Z. Yu, S. Gao, K. Shibata, M. Hirschberger, Y. Yamasaki, H. Sagayama, H. Nakao, L. C. Peng, K. Nakajima, R. Takagi, T. Arima, Y. Tokura, S. Seki
    Nature Nanotechnology 15, 444 (2020). (arXiv:2003.00626)




24. “Creation of magnetic skyrmions by surface acoustic waves”
    T. Yokouchi, S. Sugimoto, B. Rana, S. Seki, N. Ogawa, S. Kasai, Y. Otani
    Nature Nanotechnology 15, 361 (2020).




25. “Controlled transformation of skyrmions and antiskyrmions in a non-centrosymmetric magnet”
    L. Peng, R. Takagi, W. Koshibae, K. Shibata, K. Nakajima, T. Arima, N. Nagaosa, S. Seki, X. Z. Yu, Y. Tokura
    Nature Nanotechnology 15, 181 (2020).




26. “Propagation dynamics of spin excitations along skyrmion strings”
    S. Seki, M. Garst, J. Waizner, R. Takagi, N. D. Khanh, Y. Okamura, K. Kondou, F. Kagawa, Y. Otani, Y. Tokura
    Nature Communications 11, 256 (2020). (arXiv:1902.10302)




27. “Emergent topological spin structures in the centrosymmetric cubic perovskite SrFeO₃“
    S. Ishiwata, T. Nakajima, J. -H. Kim, D. S. Inosov, N. Kanazawa, J. S. White, J. L. Gavilano, R. Georgii, K. M. Seemann, G. Brandl, P. Manuel, D. D. Khalyavin, S. Seki, Y. Tokunaga, M. Kinoshita, Y. W. Long, Y. Kaneko, Y. Taguchi, T. Arima, B. Keimer, Y. Tokura
    Phys. Rev. B 101, 134406 (2020). [Editor's Suggestion] (arXiv:1806.02309)




28. “Increased lifetime of metastable skyrmions by doping”
    M. T. Birch, R. Takagi, S. Seki, M. N. Wilson, F. Kagawa, A. Štefančič, G. Balakrishnan, R. Fan, P. Steadman, C. J. Ottley, M. Crisanti, R. Cubitt, T. Lancaster, Y. Tokura, P. D. Hatton
    Phys. Rev. B 100, 014425 (2019). [Editor's Suggestion] (arXiv:1809.02590)




29. “Phonon Magnetochiral Effect”
    T. Nomura, X.-X. Zhang, S. Zherlitsyn, J. Wosnitza, Y. Tokura, N. Nagaosa, S. Seki
    Phys. Rev. Lett. 122, 145901 (2019). [Editor's Suggestion, Highlighted in Physics] (arXiv:1809.08775)




30. “Magnon-photon coupling in a noncollinear magnetic insulator Cu₂OSeO₃“
    L. V. Abdurakhimov, S. Khan, N. A. Panjwani, J. D. Breeze, M. Mochizuki, S. Seki, Y. Tokura, J. J. L. Morton, and H. Kurebayashi
    Phys. Rev. B 99, 140401(R) (2019). [Editor's Suggestion] (arXiv:1802.07113)




31. “Microwave Directional Dichroism Resonant with Spin Excitations in the Polar Ferromagnet GaV₄S₈“
    Y. Okamura, S. Seki, S. Bordacs, A. Butykai, V. Tsurkan, I. Kezsmarki, and Y. Tokura
    Phys. Rev. Lett. 122, 057202 (2019).




32. “Multiple-q non-collinear magnetism in an itinerant hexagonal magnet”
    R. Takagi, J. S. White, S. Hayami, R. Arita, D. Honecker, H. M. Ronnow, Y. Tokura, S. Seki
    Science Advances 4, 3402 (2018).




33. “Low-field bi-skyrmion formation in a noncentrosymmetric chimney ladder ferromagnet”
    R. Takagi, X. Z. Yu, J. S. White, K. Shibata, Y. Kaneko, G. Tatara, H. M. Ronnow, Y. Tokura, S. Seki
    Phys. Rev. Lett. 120, 037203 (2018).




34. “Uniaxial-stress Effects on Helimagnetic Orders and Skyrmion Lattice in Cu₂OSeO₃“
    T. Nakajima, V. Ukleev, K. Ohishi, H. Oike, F. Kagawa, S. Seki, K. Kakurai, Y. Tokura, T. Arima
    J. Phys. Soc. Jpn. 87, 094709 (2018).




35. “Stabilization of magnetic skyrmions by uniaxial tensile strain”
    S. Seki, Y. Okamura, K. Shibata, R. Takagi, N. D. Khanh, F. Kagawa, T. Arima, Y. Tokura
    Phys. Rev. B 96, 220404(R) (2017).




36. “Emergence and magnetic-field variation of chiral-soliton lattice and skyrmion lattice in the strained helimagnet Cu₂OSeO₃“
    Y. Okamura, Y. Yamasaki, D. Morikawa, T. Honda, V. Ukleev, H. Nakao, Y. Murakami, K. Shibata, F. Kagawa, S. Seki, T. Arima, and Y. Tokura
    Phys. Rev. B 96, 174417 (2017).




37. “Nonlinear Ultrafast Spin Scattering in the Skyrmion Phase of Cu₂OSeO₃“
    M. C. Langner, S. Roy, S. W. Huang, J. D. Koralek, Y.-D. Chuang, G. L. Dakovski, J. J. Turner, J. S. Robinson, R. N. Coffee, M. P. Minitti, S. Seki, Y. Tokura, R. W. Schoenlein
    Phys. Rev. Lett. 119, 107204 (2017).




38. “Spin-wave spectroscopy of the Dzyaloshinskii-Moriya interaction in room-temperature chiral magnets hosting skyrmions”
    R. Takagi, D. Morikawa, K. Karube, N. Kanazawa, K. Shibata, G. Tatara, Y. Tokunaga, T. Arima, Y. Taguchi, Y. Tokura, S. Seki
    Phys. Rev. B 95, 220406(R) (2017). (arXiv:1705.09001)




39. “Directional electric-field induced transformation from skyrmion lattice to distinct helices in multiferroic Cu₂OSeO₃“
    Y. Okamura, Y. Yamasaki, D. Morikawa, T. Honda, V. Ukleev, H. Nakao, Y. Murakami, K. Shibata, F. Kagawa, S. Seki, T. Arima, Y. Tokura.
    Phys. Rev. B 95, 184411 (2017).




40. “Thermal stability and irreversibility of skyrmion-lattice phases in Cu₂OSeO₃“
    K. Makino, J. D. Reim, D. Higashi, D. Okuyama, T. J. Sato, Y. Nambu, E. P. Gilbert, N. Booth, S. Seki, Y. Tokura
    Phys. Rev. B 95, 134412 (2017). (arXiv:1608.06359)




41. “Transition to and from the skyrmion lattice phase by electric fields in a magnetoelectric compound”
    Y. Okamura, F. Kagawa, S. Seki, and Y. Tokura
    Nature Communications 7, 12669 (2016).




42. “Magnetic reversal of electric polarization with fixed chirality of magnetic structure in a chiral-lattice helimagnet MnSb₂O₆“
    M. Kinoshita, S. Seki, T. J. Sato, Y. Nambu, T. Hong, M. Matsuda, H. Cao, S. Ishiwata, and Y. Tokura
    Phys. Rev. Lett. 117, 047201 (2016).




43. “Magnetochiral nonreciprocity of volume spin wave propagation in chiral-lattice ferromagnets”
    S. Seki, Y. Okamura, K. Kondou, K. Shibata, M. Kubota, R. Takagi, F. Kagawa, M. Kawasaki, G. Tatara, Y. Otani, and Y. Tokura
    Phys. Rev. B 93, 235131 (2016). (arXiv:1505.02868)




44. “Thermal generation of spin current in a multiferroic helimagnet”
    R. Takagi, Y. Tokunaga, T. Ideue, Y. Taguchi, Y. Tokura and S. Seki
    APL Mater. 4, 032502 (2016). [invited] (arXiv:1602.04011)




45. “Thermal generation of spin current in an antiferromagnet”
    S. Seki, T. Ideue, M. Kubota, Y. Kozuka, R. Takagi, M. Nakamura, Y. Kaneko, M. Kawasaki, and Y. Tokura
    Phys. Rev. Lett. 115, 266601 (2015). [Editor's Suggestion, Highlighted in Nature Nanotechnology and Physics] (arXiv:1508.02555)




46. “Microwave Magnetochiral Dichroism in the Chiral-Lattice Magnet Cu₂OSeO₃“
    Y. Okamura, F. Kagawa, S. Seki, M. Kubota, M. Kawasaki, and Y. Tokura
    Phys. Rev. Lett. 114, 197202 (2015).




47. “Ultrafast optical excitation of magnetic skyrmions”
    N. Ogawa, S. Seki and Y. Tokura
    Scientific Reports 5, 9552 (2015).




48. “Magnetochiral dichroism resonant with electromagnons in a helimagnet”
    S. Kibayashi, Y. Takahashi, S. Seki, and Y. Tokura
    Nature Communications 5, 4583 (2014).




49. “Coupled skyrmion sublattices in Cu₂OSeO₃“
    M.C. Langner, S. Roy, S. K. Mishra, J. C. T. Lee, X. W. Shi, M. A. Hossain, Y.-D. Chuang, S. Seki, Y. Tokura, S. D. Kevan, and R. W. Schoenlein
    Phys. Rev. Lett. 112, 167202 (2014). (arXiv:1402.2947)




50. “Thermally driven ratchet motion of a skyrmion microcrystal and topological magnon Hall effect”
    M. Mochizuki, X. Z. Yu, S. Seki, N. Kanazawa, W. Koshibae, J. Zang, M. Mostovoy, Y. Tokura, and N. Nagaosa
    Nature Materials 13, 241 (2014).




51. “Microwave magnetoelectric effect via skyrmion resonant modes in a helimagnetic multiferroics”
    Y. Okamura, F. Kagawa, M. Mochizuki, M. Kubota, S. Seki, S. Ishiwata, M. Kawasaki, Y. Onose, and Y. Tokura
    Nature Communications 4, 2391 (2013).




52. “Optimal T_c for electron-doped cuprate realized under high pressure”
    S. Ishiwata, D. Kotajima, N. Takeshita, C. Terakura, S. Seki, and Y. Tokura
    J. Phys. Soc. Jpn. 82, 063705 (2013).




53. “Superconductivity in Cu_xIrTe₂ driven by interlayer hybridization”
    M. Kamitani, M. S. Bahramy, R. Arita, S. Seki, T. Arima, Y. Tokura, and S. Ishiwata
    Phys. Rev. B 87, 180501 (2013).




54. “Magnetoelectric resonances and predicted microwave diode effect of the skyrmion crystal in a multiferroic chiral-lattice magnet”
    M. Mochizuki and S. Seki
    Phys. Rev. B 87, 134403 (2013). (arXiv:1303.4491v1)




55. “Magnetoelectric responses induced by domain rearrangement and spin structural change in triangular-lattice helimagnets NiI₂ and CoI₂“
    T. Kurumaji, S. Seki, S. Ishiwata, H. Murakawa, Y. Kaneko, and Y. Tokura
    Phys. Rev. B 87, 014429 (2013).




56. “Magnetoelectric nature of skyrmions in a chiral magnetic insulator Cu₂OSeO₃“
    S. Seki, S. Ishiwata, and Y. Tokura
    Phys. Rev. B 86, 060403(R) (2012). (arXiv:1206.4404v1)




57. “Observation of magnetic excitations of skyrmion crystal in a helimagnetic insulator Cu₂OSeO₃“
    Y. Onose, Y. Okamura, S. Seki, S. Ishiwata, and Y. Tokura
    Phys. Rev. Lett. 109, 037603 (2012). (arXiv:1204.5009v1)




58. “Formation and rotation of skyrmion crystal in the chiral-lattice insulator Cu₂OSeO₃“
    S. Seki, J.-H. Kim, D. S. Inosov, R. Georgii, B. Keimer, S. Ishiwata, and Y. Tokura
    Phys. Rev. B 85, 220406(R) (2012). (arXiv:1206.5220v1)




59. “Observation of Skyrmions in a Multiferroic Material”
    S. Seki, X. Z. Yu, S. Ishiwata, and Y. Tokura
    Science 336, 198 (2012).




60. “Magnetic-field induced competition of two multiferroic orders in a triangular-lattice helimagnet MnI₂“
    T. Kurumaji, S. Seki, S. Ishiwata, H. Murakawa, Y. Tokunaga, Y. Kaneko, and Y. Tokura
    Phys. Rev. Lett. 106, 167206 (2011). (arXiv:1103.5294v1)




61. “Effect of Spin Dilution on the Magnetic State of Delafossite CuCrO₂ with an S = 3/2 Antiferromagnetic Triangular Sublattice”
    T. Okuda, K. Uto, S. Seki, Y. Onose, Y. Tokura, R. Kajimoto, and M. Matsuda
    J. Phys. Soc. Jpn. 80, 014711 (2011).




62. “Electromagnons in the spin collinear state of a triangular lattice antiferromagnet”
    S. Seki, N. Kida, S. Kumakura, R. Shimano, and Y. Tokura
    Phys. Rev. Lett. 105, 097207 (2010). (arXiv:1008.4709v1)




63. “Cupric chloride CuCl₂ as an S = 1/2 chain multiferroic”
    S. Seki, T. Kurumaji, S. Ishiwata, H. Matsui, H. Murakawa, Y. Tokunaga, Y. Kaneko, T. Hasegawa, and Y. Tokura
    Phys. Rev. B 82, 064424 (2010). (arXiv:1008.5226v1)




64. “Electronic structure, magnetic, and dielectric properties of the edge-sharing copper oxide chain compound NaCu₂O₂“
    Ph. Leininger, M. Rahlenbeck, M. Raichle, B. Bohnenbuck, A. Maljuk, C. T. Lin, B. Keimer, E. Weschke, E. Schierle, S. Seki, Y. Tokura, and J. W. Freeland
    Phys. Rev. B 81, 085111 (2010). (arXiv:0912.0168v1)




65. “Magnetic digital flop of ferroelectric domain with fixed spin chirality in a triangular lattice helimagnet”
    S. Seki, H. Murakawa, Y.Onose, and Y. Tokura
    Phys. Rev. Lett. 103, 237601 (2009). (arXiv:0906.0324v2)




66. Effect of Quenched Disorder on Charge Ordering Structure in RE_1.67AE_0.33NiO₄ (RE = La, Pr, Nd, Sm; AE = Ca, Sr)
    X. Yu, T. Arima, S. Seki, T. Asaka, K. Kimoto, Y. Tokura, and Y. Matsui
    J. Phys. Soc. Jpn. 77, 093709 (2008).




67. “Spin-driven ferroelectricity in triangular lattice antiferromagnets ACrO₂ (A = Cu, Ag, Li, or Na) “
    S. Seki, Y.Onose, and Y. Tokura
    Phys. Rev. Lett. 101, 067204 (2008). (arXiv:0801.3757v1)




68. “Correlation between spin helicity and electric polarization vector in quantum-spin chain magnet LiCu₂O₂“
    S. Seki, Y. Yamasaki, M. Soda, M. Matsuura, K. Hirota, Y. Tokura
    Phys. Rev. Lett. 100, 127201 (2008). (arXiv:0801.2533v1)




69. “Impurity-doping-induced ferroelectricity in the frustrated antiferromagnet CuFeO₂“
    S. Seki, Y. Yamasaki, Y. Shiomi, S.Iguchi, Y.Onose, and Y. Tokura
    Phys. Rev. B 75, 100403(R) (2007). (arXiv:cond-mat/0611255v1)

Review Article

1. “Noncentrosymmetric magnets hosting magnetic skyrmions”
   N. Kanazawa, S. Seki, Y. Tokura
   Adv. Mater. 29, 1603227 (2017).




2. “Dynamical magnetoelectric phenomena of multiferroic skyrmions”
   M. Mochizuki, S. Seki
   J. Phys.: Condens. Matter 27, 503001 (2015). (arXiv:1511.07761)




3. “Multiferroics of spin origin”
   Y. Tokura, S. Seki, N. Nagaosa
   Rep. Prog. Phys. 77, 076501 (2014).




4. “Multiferroics with spiral spin orders”
   Y. Tokura, S. Seki
   Adv. Mater. 22, 1554 (2010).

Book

1. “Skyrmions in Magnetic Materials”
   S. Seki, M. Mochizuki
   (2015, Springer, ISBN 978-3-319-24649-9)
2. “Magnetoelectric Response in Low-Dimensional Frustrated Spin Systems”
   S. Seki
   (2012, Springer, ISBN 978-4-431-54090-8)

Invited Talk

1. “Topological spin textures in centrosymmetric/van der Waals magnets”
   (American Physical Society (APS) March Meeting, Minneapolis (USA), 7/Mar/2024)
   S. Seki




2. “Nanometric Skyrmions in Centrosymmetric Magnets”
   (META 2023, Paris (France), 20/July/2023)
   S. Seki




3. “Novel materials with magnetic skyrmions and their three-dimensional dynamics”
   (Superstripes 2023, Ischia-Naples (Italy), 30/June/2023)
   S. Seki




4. “Novel materials with magnetic skyrmions and their three-dimensional dynamics”
   (Workshop on Topology in Magnetic Materials, Herzberg (Switzerland), 23/Nov/2022)
   S. Seki




5. “Direct Visualization of the Three-dimensional Shape of Skyrmion Strings”
   (Materials Research Society (MRS) Spring Meeting, Honolulu (USA), 12/May/2022)
   S. Seki




6. “Skyrmions in Centrosymmetric Magnets”
   (Materials Research Society (MRS) Fall Meeting, Online [Boston (USA)], Nov/2020)
   S. Seki




7. “Coherent signal transfer along skyrmion strings”
   (British-German WE-Heraeus-Seminar “Skyrmions in Magnetic Materials”, Bad Honnef (Germany), 3/Dec/2019)
   S. Seki




8. “Propagating spin excitations along skyrmion strings”
   (Annual Conference on Magnetism and Magnetic Materials (MMM), Las Vegas (USA), 8/Nov/2019)
   S. Seki




9. “Coherent signal transfer along skyrmion strings”
   (The Future of Topological Materials, Princeton (USA), 5/Oct/2019)
   S. Seki




10. “Coherent propagation of spin excitations along skyrmion strings”
    (Magnonics, Carovigno (Italy), 29/Jul/2019)
    S. Seki




11. “Coherent signal transfer along skyrmion strings”
    (Kavli ITS-APW-Tsinghua-RIKEN Workshop, Beijing (China), 1/Nov/2018)
    S. Seki




12. “Skyrmions in Chiral Multiferroic Insulators”
    (International Conference on Magnetism (ICM), San Francisco (USA), 20/Jul/2018)
    S. Seki




13. “Coherent signal transfer through skyrmion strings”
    (Sol-Skymag, San Sebastian (Spain), 18/Jun/2018)
    S. Seki




14. “Magnetoelectric Dynamics of Skyrmions”
    (Skyrmionics: Materials, Phenomena and Applications, Santa Fe (USA), 7/Aug/2017)
    S. Seki




15. “Thermal generation of spin current in antiferromagnets and helimagnets”
    (Annual Conference on Magnetism and Magnetic Materials (MMM), New Orleans (USA), 1/Nov/2016)
    S. Seki




16. “Emergent phenomena in chiral-lattice ferromagnetic insulators”
    (Asia Pacific Center for Theoretical Physics (APCTP) Workshop on Multiferroics, Shanghai (China), 9/Oct/2016)
    S. Seki




17. “Control of skyrmions by electric field and mechanical strain”
    (International Workshop on Topological Structures in Ferroic Materials, Dresden (Germany), 19/Aug/2016)
    S. Seki




18. “Chirality and Ferromagnetism”
    (Gordon Research Conference on Multiferroic and Magnetoelectric Materials, Lewiston (USA), 10/Aug/2016)
    S. Seki




19. “Spin current in antiferromagnets and multiferroics”
    (Spin Caloritronics 7, Utrecht (Netherland), 15/Jul/2016)
    S. Seki




20. “Spin dynamics in chiral multiferroic insulators with magnetic skyrmions”
    (International Workshop on Topological Structures in Ferroic Materials, Sydney (Australia), 20/May/2015)
    S. Seki




21. “Magnetoelectric Skyrmions in Multiferroics”
    (IEEE International Magnetics Conference (INTERMAG), Beijing (China), 15/May/2015)
    S. Seki




22. “Observation and Manipulation of Magnetic Skyrmions”
    (Annual Meeting of German Physical Society (DPG), Berlin (Germany), 18/Mar/2015)
    S. Seki




23. “Skyrmions in Multiferroic Insulator”
    (Congress and general assembly of International Union of Crystallography (IUCr), Montreal (Canada), 12/Aug/2014)
    S. Seki




24. “Observation and Manipulation of Multiferroic Skyrmions”
    (SKYMAG, Paris (France), 11/Apr/2014)
    S. Seki




25. “Skyrmions in multiferroic insulator Cu₂OSeO₃“
    (Super-PIRE REIMEI Workshop on Frontiers of Condensed Matter Physics, Beijing (China), 18/Mar/2014)
    S. Seki




26. “Observation and manipulation of skyrmions in multiferroics”
    (Annual Magnetism and Magnetic Materials (MMM) Conference, Denver (USA), 8/Nov/2013)
    S. Seki




27. “Multiferroic Skyrmions”
    (APCTP Workshop on Multiferroics, Singapore, 23/May/2013)
    S. Seki




28. “Observation of Skyrmions in a Multiferroic Material”
    (American Physical Society (APS) March Meeting, Baltimore (USA), 18/Mar/2013)
    S. Seki




29. “Magnetoelectric skyrmion in a Multiferroic Material”
    (International Symposium on Integrated Functionalities (ISIF), Hong Kong (China), 20/Jun/2012)
    S. Seki

Talk

1. “Spontaneous topological Hall effect induced by non-coplanar antiferromagnetic order in intercalated van der Waals materials CoTa₃S₆ and CoNb₃S₆“
   (2023 American Physical Society March Meeting, Las Vegas, (A55.00010))
   S. Seki, H. Takagi, R. Takagi, S. Minami, T. Nomoto, K. Ohishi, M.-T. Suzuki, Y. Yanagi, M. Hirayama, N. D. Khanh, K. Karube, H. Saito, D. Hashizume, R. Kiyanagi, Y. Tokura, R. Arita, T. Nakajima




2. “Skyrmions in Multiferroics”
   (2012 American Physical Society March Meeting, Boston, (Q32.00001))
   S. Seki, X. Z. Yu, S. Ishiwata, and Y. Tokura




3. “Transition-metal dihalide MX₂ as magnetoelectric multiferroics”
   (2011 American Physical Society March Meeting, Dallas, (V22.00002))
   S. Seki, T. Kurumaji, S. Ishiwata, H. Matsui, H. Murakawa, Y. Tokunaga, Y. Kaneko, T. Hasegawa, and Y. Tokura




4. “Spin-driven ferroelectricity in triangular lattice antiferromagnets ACrO₂ (A = Cu, Ag, Li, or Na)”
   (2009 American Physical Society March Meeting, Pittsburgh, (L30.00008))
   S. Seki, Y. Onose, and Y. Tokura




5. “Correlation between spin helicity and electric polarization vector in quantum chain magnet LiCu₂O₂“
   (2008 American Physical Society March Meeting, New Orleans, (X23.00004))
   S. Seki, Y. Yamasaki, M. Soda, M. Matsuura, K. Hirota, and Y. Tokura
   
   (For other talks in Japan, please see a Japanese version of the page.)

Thesis

• “Magnetoelectric response in low-dimensional frustrated spin systems”
  Ph.D Thesis (Sep. 2010, Duke’s award)

Award

1. Dean’s Award (Research)
   (Mar. 2022, School of Engineering, University of Tokyo)
2. Marubun Research Encouragement Award
   (Mar. 2022, Marubun Research Promotion Foundation)
   “For discovery of novel skyrmion-hosting materials and their nontrivial functions”
3. IUPAP Young Scientist Prize in Magnetism
   (Jul. 2018, The International Union of Pure and Applied Physics (IUPAP))
   “For discovery of multiferroic behavior and electrically controllable skyrmions in insulating chiral magnets”
4. The Young Scientists’ Prize (The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology)
   (Apr. 2014 Ministry of Education, Culture, Sports, Science and Technology)
   “Electric control of Magnetism”
5. Young Scientist Award of the Physical Society of Japan
   (Mar. 2014 The Physical Society of Japan)
   “Observation of Magnetic Skyrmions in a Multiferroic Material”
6. Inoue Research Award for Young Scientists
   (Feb. 2012, Inoue Foundation for Science)
   “Magnetoelectric response in low-dimensional frustrated spin systems”