Takumi Hasegawa

Last Updated :2020/07/01

Affiliations, Positions
Graduate School of Advanced Science and Engineering, Associate Professor
E-mail
hasehiroshima-u.ac.jp

Basic Information

Academic Degrees

  • Doctor of Science, Tokyo Institute of Technology
  • Master of Science, Tokyo Institute of Technology

Research Fields

  • Mathematical and physical sciences;Physics;Condensed matter physics II

Research Keywords

  • rattling
  • electron-lattice interaction
  • anharmonicity

Educational Activity

Course in Charge

  1. 2020, Liberal Arts Education Program1, 1Term, Experimental Methods and Laboratory Work in Physics I
  2. 2020, Liberal Arts Education Program1, 3Term, Experimental Methods and Laboratory Work in Physics I
  3. 2020, Liberal Arts Education Program1, 2Term, Experimental Methods and Laboratory Work in Physics II
  4. 2020, Liberal Arts Education Program1, 4Term, Experimental Methods and Laboratory Work in Physics II
  5. 2020, Undergraduate Education, First Semester, Fundamental Laboratory Work in Physics
  6. 2020, Undergraduate Education, First Semester, Basic Experimental Methods for Physics
  7. 2020, Undergraduate Education, 1Term, Introduction to Physical Sciences
  8. 2020, Undergraduate Education, 3Term, Laboratory Work in Material Sciences A
  9. 2020, Undergraduate Education, 3Term, Experimental Methods for Materials Sciencs A
  10. 2020, Undergraduate Education, 2Term, Laboratory Work in Material Sciences D
  11. 2020, Undergraduate Education, 4Term, Solid State Physics I
  12. 2020, Graduate Education (Master's Program) , 2Term, Fundamentals of Complex Matter
  13. 2020, Graduate Education (Master's Program) , 3Term, Correlated Materials Science

Research Activities

Academic Papers

  1. Raman spectroscopy on ternary transition metal chalcogenide Rb2Ni3S4, Journal of Alloys and Compounds, 364(1-2), 199-207, 20040211
  2. Ultrafast photo-induced metal-insulator transition in 1/4 filled organic crystal (EDO-TTF)2PF6, Journal of Physics: Conference Series, 21, 130-135, 20050301
  3. Gigantic Photoresponse in 1/4-Filled-Band Organic Salt (EDO-TTF)2PF6, Science, 307, 86-89, 20050107
  4. First-Principles Study of Structural Phase Transitions in Hexagonal KNiCl3, Journal of the Korean Physical Society, 46(1), 59-62, 20050101
  5. Elastic properties of distorted triangular lattice KNiCl3-family compounds, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 75(9), 200609
  6. Raman scattering of Type-I clathrate compounds., Physica B, 383, 134-136, 20060401
  7. Raman scattering study of the guest ion motion in caged crystals., 33-35, 20061201
  8. Dynamical properties of guest ions in the type-I clathrate compounds X8Ga16Ge30 (X=Eu, Sr, Ba)investigated by Raman scattering, Phys. Rev. B, 74, 174303 (1-5), 20061101
  9. Raman scattering investigation of skutterudite compounds, Physica B, 383(1), 128-129, 20061201
  10. Lattice dynamics calculation of infrared active modes of cuprate superconductors, PHYSICA B-CONDENSED MATTER, 383(1), 86-88, 20060815
  11. Raman scattering investigation of skutterudite compounds, PHYSICA B-CONDENSED MATTER, 383(1), 128-129, 20060815
  12. Raman scattering of type-I clathrate compounds, PHYSICA B-CONDENSED MATTER, 383(1), 134-136, 20060815
  13. Dynamical properties of guest ions in the type-I clathrate compounds X8Ga16Ge30 (X=Eu,Sr,Ba) investigated by Raman scattering, PHYSICAL REVIEW B, 74(17), 200611
  14. Raman scattering study of the skutterudite compounds, Journal of Magnetism and Magnetic Materials, 310(2), 948-950, 20070401
  15. Raman scattering study of type-I clathrate compounds: A8Ga16Ge30 (A = Eu, Sr, Ba), Journal of Magnetism and Magnetic Materials, 310(2), 954-956, 20070401
  16. Raman scattering on La3Pd20X6 (X = Si, Ge), Journal of Magnetism and Magnetic Materials, 310(2), 984-986, 20070401
  17. Raman scattering study of filled skutterudite compounds, Journal of Physics: Conference Series, 92, 012123, 20071201
  18. Raman scattering on KOs2O6, Journal of Physics: Conference Series, 9, 012124, 20071201
  19. Raman scattering of type-I clathrate compounds: A8Ga16Ge30(A = Eu, Sr, Ba) and Sr8Ga16Si30-xGex, Journal of Physics: Conference Series, 92, 012171, 20071201
  20. Low-lying optical modes in filled skutterudites using inelastic x-ray scattering techniques, Journal of Physics: Conference Series, 92, 012171, 20071201
  21. Raman scattering study of the skutterudite compounds, JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 310(2), 948-950, 200703
  22. Raman scattering study of type-I clathrate compounds: A(8)Ga(16)Ge(30) (A = Eu, Sr, Ba), JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 310(2), 954-956, 200703
  23. Raman scattering on La3Pd20X6 (X = Si, Ge), JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 310(2), 984-986, 200703
  24. Neutron Diffraction Study of Structural Intermediate Phase IV in TlCoCl3, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 77(12), 200812
  25. Raman Scattering Study of Guest Ion Motion in Cage Compounds, Journal of Physical Society of Japan, 77(SUPPLMENT), 142-147, 20080301
  26. First-priciples calculation of lattice dynamics of skutterudite compounds, 77(SUPPLEMENT), 248-250, 20080301
  27. Raman scattering of type-I clathrate compounds, 77(SUPPLEMENT), 254-256, 20080301
  28. Direct Observation of Low-Energy Sm Phonon in SmRu4P12, 77(3), 033601/4 PAGES, 20080301
  29. Raman scattering of KOs2O6, Physical Review B, 77(6), 064303/ 6 PAGES, 20080315
  30. Anomalous phonon properties in the silicide superconductor CaAlSi and SrAlSi, Physical Review B, 78(18), 184303/10 PAGES, 20081101
  31. Off-center rattling and anisotropic expansion of type-I clathrates studied by Raman scattering, PHYSICAL REVIEW LETTERS, 100(16), 20080425
  32. Off-Center Guest Vibrations and Their Effect on Lattice Thermal Conductivity in n- and p-Type beta-Ba8Ga16Sn30, JOURNAL OF ELECTRONIC MATERIALS, 38(7), 1516-1520, 200907
  33. Optical conductivity of rattling phonons in type-I clathrate Ba8Ga16Ge30, PHYSICAL REVIEW B, 79(21), 200906
  34. Raman scattering investigation of beta-pyrochlore osmium oxides, AOs2O6 (A=K, Rb, and Cs), Journal of Physics: Conference Series, 150, 052067, 20090401
  35. Crystal Field Excitations of Filled Skutterudite PrRu4P12 by Raman Scattering, Journal of Physics: Conference Series, 150, 042147, 20090401
  36. Valence dependence of interatomic interactions in RB6, Journal of Physics: Conference Series, 176, 0120131, 20090701
  37. Raman scattering of rare earth hexaborides, Journal of Physics: Conference Series, 176, 012032, 20090701
  38. 149Sm nuclear resonant inelastic scattering of SmB6, Journal of Physics: Conference Series, 176, 012033, 20090701
  39. Off-center rattling and cage vibration of the carrier-tuned type-I clathrate Ba8Ga16Ge30 studied by Raman scattering, PHYSICAL REVIEW B, 82(13), 20101005
  40. Lattice dynamical study of alkaline atom vibrations with anharmonic interactions in beta-pyrochlore oxides, PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, 470, S695-S696, 201012
  41. Raman scattering study in iridium pyrochlore oxides, Journal of Physics: Conference Series, 200, 012054, 20100201
  42. Off-center rattling modes and glasslike thermal conductivity in the type-I clathrate Ba8Ga16Sn30, Physical Review B, 81(20), 205207, 20100501
  43. Raman scattering study of nano-particle BaTiO3, Chinese Journal of Physics, 49(1), 49-55, 20110201
  44. Raman scattering of hydrogen storage material LiNH2, Chinese Journal of Physics, 49(1), 294-300, 20110201
  45. Structural transition of RhSb3 under high pressures, Chinese Journal of Physics, 49(1), 323-330, 20110201
  46. Raman spectral analysis of metal-insulator transitions in skutterudite compound PrRu4P12, Chinese Journal of Physics, 49(1), 471-479, 20110201
  47. Low temperature phase of YbPd investigated by Raman scattering, Journal of Physics: Conference Series, 273(1), 012030/1-012030/4, 20110201
  48. Raman Scattering of YB6, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 80, 201107
  49. Raman scattering investigation on YbPd, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 80, 201107
  50. Raman scattering study of lattice dynamics in caged compounds, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 80, 201107
  51. The anharmonic vibration of Li in lithium amide, APPLIED PHYSICS LETTERS, 100(15), 20120409
  52. Tetrahedral Magnetic Order and the Metal-Insulator Transition in the Pyrochlore Lattice of Cd2Os2O7, PHYSICAL REVIEW LETTERS, 108(24), 20120613
  53. Raman Scattering Study of Hydrogen Storage Material LiNH2, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 81(9), 201209
  54. Renormalized Motion of Dysprosium Atoms Filling Boron Cages of DyB6, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 81(11), 201211
  55. Atomic dynamics of low-lying rare-earth guest modes in heavy fermion filled skutterudites ROs4Sb12 (R = light rare-earth), PHYSICAL REVIEW B, 86(19), 20121112
  56. Origins of Phase Transitions in Valence Fluctuating YbPd, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 82(8), 201308
  57. First-principles calculations of lattice vibrations on LaT2Zn20 (T = Ru and Ir), Journal of Physics: Conference Series, 391, 012016, 20130101
  58. Raman scattering spectra of LaRu2Al10 and CeRu2Al10, Journal of Physics: Conference Series, 391, 012050, 20130101
  59. Crystal Electric Field Study in Pr(Os1-xRux)4Sb12 by Raman Scattering, JPS Conf. Proc., 3, 015040/1-015040/6, 20140616
  60. Measurement of Crystal Field Excitations in NdT2Al10 (T=Ru and Os) by Raman Scattering, JPS Conf. Proc., 3, 011070/1-011070/6, 20140616
  61. Atomic Dynamics and Structural Transitions in Caged Compounds RRu2Zn20 (R=La and Pr), JPS Conf. Proc., 3, 011068/1-011068/5, 20140616
  62. Inelastic X-ray Scattering of Valence Fluctuating YbPd, JPS Conf. Proc., 3, 011037/1-011037/5, 20140616
  63. Interplay between low-energy optical phonon modes and structural transition in PrT2Zn20 (T=Ru and Ir), Journal of Physics: Conference Series, 592, 012024/1-012024/6, 20150325
  64. Valence-lattice interaction on YbPd, Journal of Physics: Conference Series, 592, 012061/1-012061/6, 20150325
  65. Inelastic X-ray Scattering Investigation of Proper Ferroelastic Transition in LiNH4C4H4O6 center dot H2O, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 85(1), 20160115
  66. Low-energy optical phonon modes in the caged compound LaRu2Zn20, PHYSICAL REVIEW B, 93(6), 20160209
  67. Guest Ion Motion in Cage Structure Crystals Investigated by Raman Scattering, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 77, 142-147, 2008
  68. Raman Scattering of Type-I Clathrate Compounds, JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 77, 254-256, 2008
  69. 15aXD-6 Raman scattering measurement of CoS_2, MnSi, and Sc_3In as itinerant electron magnet, Meeting abstracts of the Physical Society of Japan, 59(2), 20040825
  70. 27pXQ-4Raman scattering on (EDO-TTF)_2PF_6., Meeting abstracts of the Physical Society of Japan, 60(1), 20050304
  71. 22pWF-6 Raman scattering study of off-center rattling in type-I Ba_8Ga_<16>Sn_<30>, Meeting abstracts of the Physical Society of Japan, 63(2), 20080825
  72. 23pTH-8 Raman scattering of clathrate compounds Sr_8Ga_<16>Si<30-x>Ge_x II, Meeting abstracts of the Physical Society of Japan, 62(2), 20070821
  73. 28aPS-70 Inelastic X-ray scattering study of phonon dispersion in RT_2Zn_<20> (R=La, Pr, T=Ru, Ir), Meeting abstracts of the Physical Society of Japan, 69(1), 20140305
  74. Effect of rattling motion without cage structure on lattice thermal conductivity in LaOBiS2-xSex, APPLIED PHYSICS LETTERS, 112(2), 20180108
  75. Retreat from Stress: Rattling in a Planar Coordination, ADVANCED MATERIALS, 30(13), 20180327
  76. High-pressure Raman study on the superconducting pyrochlore oxide Cd2Re2O7, PHYSICA B-CONDENSED MATTER, 536, 600-603, 20180501
  77. Antiferroelectric distortion with anomalous phonon softening in the excitonic insulator Ta2NiSe5, PHYSICAL REVIEW B, 98(4), 20180730