English / Japanese

Yuki Nagai, Ph. D.

Information Technology Center, The University of Tokyo
Position : Associate Professor

2018-2023 Visiting resercher in RIKEN AIP
2016-2017:
Visiting Scholar, Department of Physics, Massachusetts Institute of Technology, USA (Host reseacher: Prof. Liang Fu)
2010-2019:
Scientist in CCSE, Japan Atomic Energy Agency (JAEA)
2019-2024:
Senior Scientist in CCSE, Japan Atomic Energy Agency (JAEA)


Email : Nagai.Yuki_-at.-mark.-_mail.u-tokyo.ac.jp (Replace _-at-mark-_ with @)



MAJOR: Condensed Matter Physics (Theory)
especially, Superconductivity

Academic Qualifications

2001-2005 : B. Eng. Department of Applied Physics, Hokkaido University.
Supervisor : Prof. H. Akera.
Subject : "Electron Temperature Distribution in Quantum Hall Systems with Potential Steps"

2005-2007 : M. Sci. Department of Physics, University of Tokyo.
Supervisor : Asso. Prof. Y. Kato.
Subject : "Analytical Theory of the Local Density of States around a Vortex in Superconductors"

2007-2010 : Ph. D. research at Department of Physics, University of Tokyo.
Supervisor : Asso. Prof. Y. Kato.
Subject : "Theoretical study of pairing symmetries in iron-based superconductors"


Awards
Mar. 2015: Young Scientist Award of the Physical Society of Japan

Preprints

  1. Akio Tomiya, Yuki Nagai, Gauge covariant neural network for 4 dimensional non-abelian gauge theory, hep-lat/arXiv:2103.11965
  2. Yuki Nagai, Akio Tomiya, Extensively parallelizable chiral fermion, hep-lat/arXiv:2204.01583
  3. Yuki Nagai, Yutaka Iwasaki, Koichi Kitahara, Yoshiki Takagiwa, Kaoru Kimura, Motoyuki Shiga, Atomic diffusion due to hyperatomic fluctuation for quasicrystals, cond-mat/2302.14441
  4. Yuki Nagai, Akio Tomiya, Self-learning Monte Carlo with equivariant Transformer, cond-mat/arXiv:2306.11527
  5. Yuita Fujisawa, Anjana Krishnadas, Barnaby R. M. Smith, Markel Pardo-Almanza, Hoshu Hiyane, Yuki Nagai, Tadashi Machida, Yoshinori Okada, Imaging Josephson Vortices on Curved Junctions, cond-mat/arXiv:2307.11970
  6. Yuita Fujisawa, Anjana Krishnadas, Chia-Hsiu Hsu, Barnaby R. M. Smith, Markel Pardo-Almanza, Yukiko Obata, Dyon van Dinter, Guoqing Chang, Yuki Nagai, Tadashi Machida, Yoshinori Okada, Visualizing magnetic field-induced rotational electronic symmetry breaking in a spinel oxide superconductor, cond-mat/arXiv:2306.06711

Papers

  1. Y. Nagai, Y. Kato and N. Hayashi, Analytical Result on Electronic States around a Vortex Core in a Noncentrosymmetric Superconductor, J. Phys. Soc. Jpn. 75 043706-1 043706-4 (2006) DOI: 10.1143/JPSJ.75.043706
  2. Y. Nagai, Y. Ueno, Y. Kato and N. Hayashi, Analytical Formulation of the Local Density of States around a Vortex Core in Unconventional Superconductors, J. Phys. Soc. Jpn. 75 104701-1 104701-14 (2006) DOI: 10.1143/JPSJ.75.104701
  3. Y. Nagai, Y. Kato, N. Hayashi, K. Yamauchi and H. Harima, Calculated Positions of Point Nodes in the Gap Structure of the Borocarbide Superconductor YNi2B2C, Phys. Rev. B 76, 214514-1 214514-8 (2007) DOI: 10.1103/PhysRevB.76.214514
  4. Y. Nagai and N. Hayashi, Kramer-Pesch approximation for analyzing field-angle-resolved measurements made in unconventional superconductors: A calculation of the zero-energy density of states, Phys. Rev. Lett. 101 097001-1 097001-4 (2008) DOI: 10.1103/PhysRevLett.101.097001
  5. Y. Nagai, N. Hayashi, N. Nakai, H. Nakamura, M. Okumura and M. Machida, Nuclear magnetic relaxation and superfluid density in Fe-pnictide superconductors: An anisotropic ±s-wave scenario, New J. Phys. 10 103026-1 103026-17 (2008) DOI:10.1088/1367-2630/10/10/103026
  6. Y. Nagai and N. Hayashi, Surface Bound States in n-band Systems with Quasiclassical Approach, Phys. Rev. B 79 224508-1 224508-9 (2009) DOI: 10.1103/PhysRevB.79.224508
  7. S. Nakakura, Y. Nagai and D. Yoshioka, Uniform current in graphene strip with zigzag edges, J. Phys. Soc. Jpn. 78 065003-1 065003-2 (2009) DOI: 10.1143/JPSJ.78.065003
  8. Y. Nagai and Y. Kato, Impurity scattering rate and coherence factor in vortex core of sign-reversing s-wave superconductors, Phys. Rev. B 82 (2010) 174507 DOI: 10.1103/PhysRevB.82.174507
  9. N. Nakai, H. Nakamura, Y. Ota, Y. Nagai, N. Hayashi, and M. Machida, First-principles-based ±pm s-wave modeling for iron-based superconductors:Studies for specific heat and nuclear magnetic relaxation rate, Phys. Rev. B 82 094501-1 094501-5 (2010) DOI: 10.1103/PhysRevB.82.094501
  10. M. Kunimi, Y. Nagai, and Y. Kato, Josephson effects in one-dimensional supersolids, Phys. Rev. B 84 094521-1 094521-9 (2011) DOI: 10.1103/PhysRevB.84.094521
  11. Y. Imai, H. Takahashi, K. Kitagawa, K. Matsubayashi, N. Nakai, Y. Nagai, Y. Uwatoko, M. Machida, A. Maeda, Microwave Surface Impedance Measurements of LiFeAs Single Crystals, J. Phys. Soc. Jpn. 80 013704-1 013704-4 (2011) DOI: 10.1143/JPSJ.80.013704 Most Cited Articles in 2012 from Vol. 80(2011)
  12. Y. Nagai, H. Nakamura, and M. Machida, Superconducting Gap Function in an Organic Superconductor (TMTSF)2ClO4 with Anion Ordering; First-principles Calculations and Quasi-classical Analyses for Angle-resolved Heat Capacity, Phys. Rev. B 83 104523-1 104523-8 (2011) DOI: 10.1103/PhysRevB.83.104523
  13. Y. Nagai, and K. Kuroki, Determination of the pairing state in iron-based superconductors through neutron scattering, Phys. Rev. B 83 220516-1 220516-4(R) (2011) DOI: 10.1103/PhysRevB.83.220516
  14. M. Ishikado, Y. Nagai, K. Kodama, R. Kajimoto, M. Nakamura, Y. Inamura, S. Wakimoto, H. Nakamura, M. Machida, K. Suzuki, H. Usui, K. Kuroki, A. Iyo, H. Eisaki, M. Arai, S. Shamoto, s±-like spin resonance in the iron-based nodal superconductor BaFe2(As0.65P0.35)2 observed using inelastic neutron scattering, Phys. Rev. B 84 144517-1 144517-5 (2011) DOI: 10.1103/PhysRevB.84.144517
  15. Y. Nagai, N. Nakai, and M. Machida, Direct Numerical Demonstration of Sign-preserving Quasiparticle Interference via Impurity inside Vortex Core in Unconventional Superconductors, Phys. Rev. B 85 092505-1 092595-4 (2012) DOI: 10.1103/PhysRevB.85.092505
  16. Y. Nagai, Y. Ota, and M. Machida, Efficient Numerical Self-consistent Mean-field Approach for Fermionic Many-body Systems by Polynomial Expansion on Spectral Density, J. Phys. Soc. Jpn. 81 024710-1 024710-6 (2012) DOI: 10.1143/JPSJ.81.024710
  17. Y. Nagai, and K. Kuroki, Q-scan-analysis of the neutron scattering in iron-based superconductors, Phys. Rev. B 85 134521-1,134521-7 (2012) DOI: 10.1103/PhysRevB.85.134521
  18. Y. Nagai, K. Tanaka, and N. Hayashi, Quasiclassical numerical method for mesoscopic superconductors: bound states in a circular d-wave island with a single vortex, Phys. Rev. B 86, 094526-1, 094526-9 (2012) DOI: 10.1103/PhysRevB.86.094526
  19. Y. Nagai, H. Nakamura, and M. Machida, Rotational Isotropy Breaking as Proof for Spin-polarized Cooper Pair in Topological Superconductor CuxBi2Se3, Phys. Rev. B 86 094507-1, 094507-5 (2012) DOI:09450710.1103/PhysRevB.86.094507
  20. Y. Nagai, Y. Shinohara, Y. Futamura, Y. Ota, and T. Sakurai, Numerical construction of a low-energy effective Hamiltonian in a self-consistent Bogoliubov-de Gennes approach of superconductivity, J. Phys. Soc. Jpn. 82 094701-1,094701-10 (2013) DOI: 10.7566/JPSJ.82.094701
  21. Y. Higashi, Y. Nagai, M. Machida, and N. Hayashi, Field-angle resolved flux-flow resistivity as a phase-sensitive probe of unconventional Cooper pairing, Phys. Rev. B 88 224511-1 224511-6 (2013) DOI: 10.1103/PhysRevB.88.224511
  22. Y. Nagai, H. Nakamura, and M. Machida, * Spin-polarized Majorana Bound States around a Vortex in Topological Superconductors *, J. Phys. Soc. Jpn. 83, 064703-1,064703-7 (2014). DOI: 10.7566/JPSJ.83.064703 'Papers of Editors' Choice'
  23. Y. Nagai, H. Nakamura, and M. Machida, Quasiclassical Treatment and Odd-parity/Triplet Correspondence in Topological Superconductors, J. Phys. Soc. Jpn. 83 053705-1,053705-4 (2014) DOI: 10.7566/JPSJ.83.053705
  24. Y. Nagai, Field-angle-dependent Low-energy Excitations around a Vortex in the Superconducting Topological Insulator CuxBi2Se3, J. Phys. Soc. Jpn. 83 063705-1,063705-4 (2014),DOI: 10.7566/JPSJ.83.063705
  25. Y. Nagai, Y. Ota, and M. Machida, Nonmagnetic impurity effects in a three-dimensional topological superconductor: From p- to s-wave behaviors, Phys. Rev. B 89, 214506-1,214506-6 (2014) DOI: 10.1103/PhysRevB.89.214506
  26. Y. Nagai, Y. Ota, and M. Machida, Impurity effects in a two-dimensional topological superconductor: A link of Tc-robustness with a topological number, J. Phys. Soc. Jpn. 83 094722-1, 094722-5 DOI: 10.7566/JPSJ.83.094722
  27. S. Yoshizawa, H. Kim, T. Kawakami, Y. Nagai, T. Nakayama, X. Hu, Y. Hasegawa, and T. Uchihashi, Imaging Josephson vortices on the surface superconductor Si(111)-(√7 x√3)-In using a scanning tunneling microscope, Phys. Rev. Lett. 113, 247004-1,247004-5, DOI: 10.1103/PhysRevLett.113.247004‘Editors' Suggestion’ ’Featured in Physics’
  28. Y. Nagai, H. Nakamura, and M. Machida, Surface states around a vortex in topological superconductors: Intersection of a surface and a vortex, J. Phys. Soc. Jpn. 84, 033703-1,033703-4 (2015). DOI: 10.7566/JPSJ.84.033703
  29. Y. Nagai, Y. Ota, and M. Machida, Topological s-wave pairing superconductivity with spatial inhomogeneity: Mid-gap-state appearance and robustness of superconductivity, J. Phys. Soc. Jpn. 84, 034711-1,034711-8 (2015). DOI:10.7566/JPSJ.84.034711
  30. Y. Nagai,Robust superconductivity with nodes in the superconducting topological insulator CuxBi2Se3: Zeeman orbital field and non-magnetic impurities, Phys. Rev. B 91, 060502(R)-1,060502(R)-5 (2015). DOI: 10.1103/PhysRevB.91.060502
  31. A. Shitade and Y. Nagai, Orbital angular momentum in a nonchiral topological superconductor, Phys. Rev. B 92, 024502-1,024502-5 (2015). DOI: 10.1103/PhysRevB.92.024502-7
  32. Y. Nagai, H. Nakamura, M. Machida, and K. Kuroki, First-principle study of antimony doping effects on the iron-based superconductor CaFe(SbxAs1-x)2, J. Phys. Soc. Jpn. 84, 093702-1,093702-4 (2015) DOI:10.7566/JPSJ.84.093702
  33. Y. Nagai, Y. Ota, and M. Machida, Inverse coherence effects in nuclear magnetic relaxation rates as a sign of topological superconductivity, Phys. Rev. B 92, 180502(R) (2015), 10.1103/PhysRevB.92.180502
  34. Y. Higashi, Y. Nagai, T. Yoshida, Y. Masaki, and Y. Yanase, Robust zero-energy bound states around a pair-density-wave vortex core in locally noncentrosymmetric superconductors, Phys. Rev. B 93, 104529 (2016),10.1103/PhysRevB.93.104529
  35. A. Shitade and Y. Nagai, Orbital angular momentum in a topological superconductor with Chern number higher than 1, Phys. Rev. B 93, 174517 (2016), DOI:10.1103/PhysRevB.93.174517
  36. Y. Nagai and H. Nakamura, Multi-band Eilenberger theory of superconductivity: Systematic low-energy projection, to be published in J. Phys. Soc. Jpn.
  37. Y. Nagai, S. Hoshino, and Y. Ota, Critical temperature enhancement of topological superconductors: A dynamical mean-field study, Phys. Rev. B 93, 220505(R) (2016), DOI: 10.1103/PhysRevB.93.220505
  38. Y. Nagai, and Y. Ota, Nuclear magnetic relaxation rates of unconventional superconductivity in doped topological insulators, Phys. Rev. B 94, 134516 (2016), DOI: 10.1103/PhysRevB.94.134516
  39. Evan D. B. Smith, K. Tanaka, and Y. Nagai, Manifestation of chirality in the vortex lattice in a two-dimensional topological superconductor, Phys. Rev. B 94, 064515 (2016), DOI: 10.1103/PhysRevB.94.064515
  40. S. Yonezawa, K. Tajiri, S. Nakata, Y. Nagai, Z. Wang, K. Segawa, Y. Ando, and Y. Maeno, Thermodynamic evidence for nematic superconductivity in CuxBi2Se3, Nature Physics 13, 123 (2017), DOI: 10.1038/nphys3907
  41. Y. Nagai, Yasushi Shinohara, Yasunori Futamura, and Tetsuya Sakurai, Reduced-Shifted Conjugate-Gradient Method for a Green's Function: Efficient Numerical Approach in a Nano-structured Superconductor, J. Phys. Soc. Jpn. 86, 014708 (2017), 10.7566/JPSJ.86.014708
  42. H. Kim, S.-Z. Lin, M. J. Graf, Y. Miyata, Y. Nagai, T. Kato, and Y. Hasegawa, Electrical Conductivity through a Single Atomic Step Measured with the Proximity-Induced Superconducting Pair Correlation, Phys. Rev. Lett 117, 116802 (2016), DOI:10.1103/PhysRevLett.117.116802
  43. Y. Nagai, Y. Ota, and K. Tanaka, Time-reversal symmetry breaking and gapped surface states due to spontaneous emergence of new order in d-wave nanoislands, Phys. Rev. B 96, 060503(R) (2017), DOI: 10.1103/PhysRevB.96.060503
  44. S. L. Goertzen, K. Tanaka, and Y. Nagai, Self-consistent study of Abelian and non-Abelian order in a two-dimensional topological superconductor, Phys. Rev. B 95, 064509 (2017), DOI: 10.1103/PhysRevB.95.064509
  45. Y. Nagai, H. Shen, Y. Qi, J. Liu, and L. Fu, Self-Learning Monte Carlo Method: Continuous-Time Algorithm, Phys. Rev. B 96, 161102(R) (2017), DOI: 10.1103/PhysRevB.96.161102
  46. K. Iida, M. Ishikado, Y. Nagai, H. Yoshida, A. D. Christianson, N. Murai, K. Kawashima, Y. Yoshida, H. Eisaki, and A. Iyo, Spin Resonance in the New-Structure-Type Iron-Based Superconductor CaKFe4As4, J. Phys. Soc. Jpn. 86 0937031-0937034 (2017), DOI: 10.7566/JPSJ.86.093703
  47. Y. Nagai and H. Shinaoka, Smooth self-energy in the exact-diagonalization-based dynamical mean-field theory: Intermediate-representation filtering approach, J. Phys. Soc. Jpn. 88, 064004 (2019), DOI: 10.7566/JPSJ.88.064004
  48. Y. Nagai and Y. Kato, Quasiparticle Bound States around Fractional Vortices in s-wave Superconductor, J. Phys. Soc. Jpn. 88, 054707 (2019), DOI:10.7566/JPSJ.88.054707
  49. K. Iida, Y. Nagai, S. Ishida, M. Ishikado, N. Murai, A. D. Christianson, H. Yoshida, Y. Inamura, H. Nakamura, A. Nakao, K. Munakata, D. Kagerbauer, M. Eisterer, K. Kawashima, Y. Yoshida, H. Eisaki, and A. Iyo, Coexisting spin resonance and long-range magnetic order of Eu in EuRbFe4As4, Phys. Rev. B 100, 014506 (2019), DOI: 10.1103/PhysRevB.100.014506
  50. M. Kheirkhah, Y. Nagai, C. Chen, F. Marsiglio, * Majorana corner flat bands in two-dimensional second-order topological superconductors *, Phys. Rev. B 101, 104502 (2020), DOI: 10.1103/PhysRevB.101.104502
  51. T. Matsushita, Y. Nagai, S. Fujimoto, Disorder-induced exceptional and hybrid rings in Weyl/Dirac semimetals, Phys. Rev. B 100, 245205 (2019), DOI:10.1103/PhysRevB.100.245205
  52. Yuki Nagai, N-independent Localized Krylov Bogoliubov-de Gennes Method: Ultra-fast Numerical Approach to Large-scale Inhomogeneous Superconductors, J. Phys. Soc. Jpn. 89, 074703 (2020)
  53. Y. Nagai, M. Okumura, and A. Tanaka, Self-learning Monte Carlo method with Behler-Parrinello neural networks, Phys. Rev. B 101, 115111 (2020), DOI:10.1103/PhysRevB.101.115111
  54. Etsuko Itou and Yuki Nagai, Sparse modeling approach to obtaining the shear viscosity from smeared correlation functions, Journal of High Energy Physics volume 2020, 7 (2020)
  55. Majid Kheirkhah, Zhongbo Yan, Yuki Nagai, Frank Marsiglio, First and second-order topological superconductivity and temperature-driven topological phase transitions in the extended Hubbard model with spin-orbit coupling, Phys. Rev. Lett. 125, 017001 (2020)
  56. Yuki Nagai, Yang Qi, Hiroki Isobe, Vladyslav Kozii, and Liang Fu, DMFT Reveals the Non-Hermitian Topology and Fermi Arcs in Heavy-Fermion Systems, Phys. Rev. Lett. 125, 227204-1, 227204-7 (2020)
  57. Yuki Nagai, Masahiko Okumura, Keita Kobayashi, and Motoyuki Shiga, Self-learning hybrid Monte Carlo: A first-principles approach, Phys. Rev. B 102, 041124(R)-1,041124(R)-6 (2020)
  58. Hiroshi Shinaoka and Yuki Nagai, Sparse modeling of large-scale quantum impurity models with low symmetries, Physical Review B 103, 045120-1, 045120-8 (2021)
  59. Hidehiko Kohshiro, and Yuki Nagai, Effective Ruderman–Kittel–Kasuya–Yosida-like Interaction in Diluted Double-exchange Model: Self-learning Monte Carlo Approach, J. Phys. Soc. Jpn. 90, 034711-1, 034711-8 (2021)
  60. Taiki Matsushita, Yuki Nagai, and Satoshi Fujimoto, Spectrum Collapse of Disordered Dirac Landau Levels as Topological Non-Hermitian Physics, J. Phys. Soc. Jpn. 90, 074703-1, 074703-9 (2021)
  61. Keita Kobayashi, Yuki Nagai, Mitsuhiro Itakura, and Motoyuki Shiga, Self-learning hybrid Monte Carlo method for isothermal-isobaric ensemble: Application to liquid silica, The Journal of Chemical Physics 155, 034106-1, 034106-9 (2021)
  62. Howon Kim, Yuki Nagai, Levente Rózsa, Dominik Schreyer, and Roland Wiesendanger, Anisotropic non-split zero-energy vortex bound states in a conventional superconductor, Applied Physics Reviews 8, 031417-1, 031417-8 (2021)
  63. Yuki Nagai, Intrinsic vortex pinning in superconducting quasicrystals, Phys. Rev B 106, 064506-1-10 (2022)
  64. Markus Wallerberger, Samuel Badr, Shintaro Hoshino, Sebastian Huber, Fumiya Kakizawa, Takashi Koretsune, Yuki Nagai, Kosuke Nogaki, Takuya Nomoto, Hitoshi Mori, Junya Otsuki, Soshun Ozaki, Thomas Plaikner, Rihito Sakurai, Constanze Vogel, Niklas Witt, Kazuyoshi Yoshimi, Hiroshi Shinaoka, sparse-ir: Optimal compression and sparse sampling of many-body propagators, SoftwareX 21 101266 1-7 (2023)
  65. T. Machida, Yuki Nagai, and T. Hanaguri, Zeeman effects on Yu-Shiba-Rusinov states, Phys. Rev. Research 4, 033182 1-12 (2022)
  66. Yuki Nagai, Akinori Tanaka, and Akio Tomiya, Self-learning Monte Carlo for non-Abelian gauge theory with dynamical fermions, Phys. Rev. D 107, 054501 1-16 (2023)
  67. Yuki Nagai, and Hiroshi Shinaoka, Sparse Modeling Approach for Quasiclassical Theory of Superconductivity, Journal of the Physical Society of Japan 92, 034703 1-8 (2023)

Proceedings

  1. Y. Nagai, H. Akera and H. Suzuura, Spatial Variations of the Hall Potential and the Electron Temperature in Quantum Hall Systems with a Filling Factor Step, The 28th International Conference on the Physics of Semiconductors, Vienna, Austria, 2006, AIP Conference Proceedings 893 665 (2007) DOI:10.1063/1.2730066
  2. Y. Nagai, N. Hayashi, Y. Kato, K. Yamauchi and H. Harima, Field angle dependence of the zero-energy density of states in unconventional superconductors: analysis of the borocarbide superconductor YNi$2$B$2$C, The 25th international conference on Low Temperature Physics (LT24), Amsterdam, The Netherlands, 2008, J. Phys.: Conf. Ser. 150 (2009) 052177 DOI:10.1088/1742-6596/150/5/052177
  3. N. Hayashi, Y. Nagai, and Y. Higashi, Analysis of field-angle dependent specific heat in unconventional superconductors: a comparison between Doppler-shift method and Kramer-Pesch approximation, The 9th International Conference on Materials and Mechanisms of Superconductivity (M2S), Tokyo, 2009, Physica C 470, (2010) S865 DOI:10.1016/j.physc.2009.10.045
  4. Y. Nagai, N. Hayashi, and M. Machida, Surface-angle dependence of the tunneling spectroscopy in iron-based superconductors: sign-reversing s-wave scenarios, The 9th International Conference on Materials and Mechanisms of Superconductivity (M2S), Tokyo, 2009, Physica C 470 (2010) S504 DOI:10.1016/j.physc.2009.10.043
  5. M. Machida, Y. Nagai, Y. Ota, N. Nakai, H. Nakamura, and N. Hayashi, Phenomenological theory for ±s-wave superconducting states of iron-based superconductors, The 9th International Conference on Materials and Mechanisms of Superconductivity (M2S), Tokyo, 2009, Physica C 470 (2010) S372 DOI:10.1016/j.physc.2009.10.087
  6. N. Nakai, H. Nakamura, Y. Ota, Y. Nagai, N. Hayashi, and M. Machida, Small jump of specific heat and small gap in iron pnictide superconductors, The 9th International Conference on Materials and Mechanisms of Superconductivity (M2S), Tokyo, 2009, Physica C 470 (2010) S368 DOI: 10.1016/j.physc.2010.01.055
  7. N. Nakai, Y. Nagai, and M. Machida, Low-lying excitations induced by non-magnetic impurities in d-wave superconductors, The 24th International Symposium on Superconductivity (ISS2010), Tsukuba, 2010, Physica C 471 (2011) 743 DOI:10.1016/j.physc.2011.05.042
  8. Y. Higashi, Y. Nagai, M. Machida and N. Hayashi, Field-angle dependence of the quasiparticle scattering inside a vortex core in unconventional superconductors, The 24th International Symposium on Superconductivity (ISS2010), Tsukuba, 2010, Physica C 471 (2011) 828 DOI: 10.1016/j.physc.2011.05.066
  9. Y. Nagai, H. Nakamura, K. Suzuki, H. Usui, K. Kuroki, and M. Machida, Theoretical analysis for inelastic neutron scattering on BaFe2(As1−xPx)2 by the realistic three-dimensional 10-orbital tight-binding model, International Workshop on Neutron Applications on Strongly Correlated Electron Systems 2011, Ibaraki, 2011, J. Phys. Soc. Jpn. 80 (2011) SB021 DOI:10.1143/JPSJS.80SB.SB021
  10. Y. Nagai, Y. Ota, and M. Machida, Spectral-density polynomial expansion for two-particle Green's function in BdG framework, The 24th International Symposium on Superconductivity (ISS2011), Tokyo, 2011, Physics Procedia 27 (2012) 72 DOI:10.1016/j.phpro.2012.03.413
  11. Y. Higashi, Y. Nagai, M. Machida, and N. Hayashi, Phase-Sensitive Flux-Flow resistivity in Unconventional Superconductors, The 26th International Conference on Low Temperature Physics (LT26), Beijing, China, 2011, J. Phys.: Conf. Ser. 400, (2012) 022025 DOI:10.1088/1742-6596/400/2/022025
  12. Y. Higashi, Y. Nagai, M. Machida, and N. Hayashi, Effect of uniaxially anisotropic Fermi surface on the quasiparticle scattering inside a vortex core in unconventional superconductors, the 24th International Symposium on Superconductivity (ISS2011), Tokyo, 2011 Physica C 484 (2013) 97 DOI: 10.1016/j.physc.2012.03.038
  13. Y. Nagai, H. Nakamura, and M. Machida, Andreev Bound-states of vortices and surfaces in topological superconductors, International Conference Dubna-Nano, Dubna, Russia, 2012, J. Phys.: Conf. Ser. 393 (2012) 012017 DOI: 10.1088/1742-6596/393/1/012017
  14. Y. Higashi, Y. Nagai, M. Machida, and N. Hayashi, Effect of Anisotropic Fermi Surface on the Flux-flow Resistivity under Rotating Magnetic Field, the 25th International Symposium on Superconductivity (ISS2012), Tokyo, 2012, Physics Procedia 45 (2013) 137, DOI:10.1016/j.phpro.2013.04.071
  15. J. W. Sadowski, K. Tanaka, and Y. Nagai, Effects of band structure and electron–phonon coupling on charge density waves, Theory Canada 7, Lethbridge, Canada, 2012, Canadian Journal of Physics, 91 (2013) 487 DOI: 10.1139/cjp-2012-0440
  16. Y. Nagai, H. Nakamura, M. Machida, Surface and vortex bound states in topological superconductors, The 25th International Symposium on Superconductivity (ISS2012), Tokyo, 2012, Physica C 494 (2013) 17 DOI: 10.1016/j.physc.2013.04.018
  17. T. Yamane, Y. Nagai, K. Tanaka, and N. Hayashi, Impurity scattering effect on the zero-energy peak of the local density of states in a multi-quantum vortex core, The 25th International Symposium on Superconductivity (ISS2012), Tokyo, 2012, Physica C 494 (2013) 128 Physica C DOI:10.1016/j.physc.2013.04.046
  18. Y. Higashi, Y. Nagai and N. Hayashi, Impurity Effect on the Local Density of States around a Vortex in Noncentrosymmetric Superconductors, Proc. Int. Conf. Strongly Correlated Electron Systems (SCES2013), JPS Conf. Proc. 3, 015003 (2014) , DOI: 10.7566/JPSCP.3.015003
  19. Y. Nagai, H. Nakamura, and M. Machida, Inhomogeneity Effects in Topological Superconductors, Proc. Int. Conf. Strongly Correlated Electron Systems (SCES2013), JPS Conf. Proc. 3, 015013 (2014) , DOI: 10.7566/JPSCP.3.015013
  20. Y. Nagai, Y. Ota and M. Machida, Robustness against non-magnetic impurities in topological superconductors, J. Phys.: Conf. Ser. 568, 022030 (2014), DOI:10.1088/1742-6596/568/2/022030
  21. Y. Higashi, Y. Nagai, T. Yoshida and Y. Yanase, Vortex Core Structure in Multilayered Rashba Superconductors, J. Phys.: Conf. Ser. 568, 022018 (2014), DOI:10.1088/1742-6596/568/2/022018
  22. T. Kawakami, Y. Nagai, S. Yoshizawa, H. Kim, Y. Hasegawa, T. Nakayama, T. Uchihashi and X. Hu, Excitation spectrum of Josephson vortices on surface superconductor, J. Phys.: Conf. Ser. 568, 022022 (2014), DOI:10.1088/1742-6596/568/2/022022
  23. Y. Ota, Y. Nagai, and M. Machida, Theory of low-energy behaviors in topological s-wave pairing superconductors, Physica C 518, 5-9 (2015),doi:10.1016/j.physc.2015.08.002
  24. Y. Higashi, Y. Nagai, T. Yoshida, M. Kato, and Y. Yanase, Excitation spectra and wave functions of quasiparticle bound states in bilayer Rashba superconductors, Physica C 518 1-4 (2015),doi:10.1016/j.physc.2015.03.004

Doctor Thesis

Y. Nagai
Theoretical study of pairing symmetries in iron-based superconductors (in Japanese)
Doctor Thesis (Univ. of Tokyo)
[PDF]


Master Thesis

Y. Nagai
Analytical Theory of the Local Density of States around a Vortex in Superconductors (in Japanese)
Master Thesis (Univ. of Tokyo)
[PDF]


Graduation Thesis

Y. Nagai
Electron Temperature Distribution in Quantum Hall Systems with Potential Steps
Graduation Thesis (Hokkaido Univ.)
[PDF]


Collaborator's link
Yoich Higashi (Osaka Prefecture University)

top