2001 Fiscal Year Annual Research Report

磁場が誘起するマグノンのボース・アインシュタイン凝縮と局在

Research Project

Project/Area Number	13130202
Research Category	Grant-in-Aid for Scientific Research on Priority Areas (B)
Research Institution	Tokyo Institute of Technology
Principal Investigator	田中秀数東京工業大学, 大学院・理工学研究科, 助教授 (80188325)
Co-Investigator(Kenkyū-buntansha)	細越裕子岡崎国立共同研究機構, 分子科学研究所, 助手 (50290903) 小野俊雄東京工業大学, 大学院・理工学研究科, 助手 (40332639) 押川正毅東京工業大学, 大学院・理工学研究科, 助教授 (50262043)
Keywords	スピンギャップ / マグノン / ボース・アインシュタイン凝縮 / ESR / 磁場誘起相転移 / 磁化プラトー / TlCuCl_3 / BIP-TENO
Research Abstract	科研費特定領域研究(B)の支援の下で,本年度は以下の研究実績を上げた. 1.スピンギャップ系TlCuCl_3の磁気励起を中性子非弾性散乱によって詳細に調べ,最低励起エネルギーを与える逆格子点と磁気励起の分散関係を決定した.また有効ダイマー相互作用模型とクラスター展開法によって分散関係を解析し,交換相互作用を求めた. 2.TlCuCl_3の磁場誘起相転移はマグノンのボース・アインシュタイン凝縮(ボース凝縮)として捉えられることが我々の研究から分かった.理論的には秩序相では磁場に垂直なスピン成分が秩序化する.この横成分秩序を磁場中中性子弾性散乱によって確認した.また凝縮体密度に対応する磁気ブラッグ散乱強度の温度及び磁場依存性を詳細に求めた. 3.結晶構造が同じTlCuCl_3とKCuCl_3の混晶Tl_<1-x>K_xCuCl_3を作成して,交換相互作用にランダムネスを導入し,ランダムネスが磁場誘起相転移に及ぼす効果を磁化測定によって調べた.ランダムネスが入ると,マグノンに局在の傾向が現れ,相転移温度は低下することが分かった. 4.大きな単イオン異方性D(S_z)^2のために基底1重項となる3角格子反強磁性体CsFeBr_3において磁場誘起相転移を磁化と比熱測定で調べ,この相転移が2段階に起きることを見出した. 5.Mnイオンが5価であるBa_3Mn_2O_8の磁化測定を行い,この物質がスピンギャップを持つこと,及び磁化プラトーを見出した.また磁化曲線を平均場近似で解析し,交換相互作用を見積もった. 6.有機物磁性体BIP-TENOを合成し,これがS=1のスピンラダーとして記述できることを示した.また強磁場磁化測定から飽和磁化の1/4に磁化プラトーを発見した. 7.有機物磁性体BIPNNBNOを合成し,これがS=1/2とS=1の混合スピン系として記述されることを示した.また強磁場磁化測定から飽和磁化の1/3に磁化プラトーを発見した. 8.S=1/2の1次元反強磁性体の電子スピン共鳴線幅の温度変化を場の理論を用いて研究し,従来の定説を覆す結果を得た.

Research Products

(48 results)

All Other

All Publications (48 results)

[Publications] M.Reehuis: "Partial Frustration of the Copper Spins in RbCuCl_3"J. Phys. Chem. Solids. 62. 1139-1143 (2001)
[Publications] B.Wolf: "Ultrasonic Experiments in SrCu_2(BO_3)_2, and NH_4CuCl_3 in Magnetic Fields up to 50T"J. Magn. & Magn. Mater.. 226. 1139-1143 (2001)
[Publications] K.Kakurai: "Neutron Scattering Experiments on Low-Dimensional Quantum Spin Systems -Spin Excitations in KCuCl_3 and SrCu_2(BO_3)_2 -"J. Phys. Chem. Solids. 62. 141-147 (2001)
[Publications] T.Ono: "Oblique Triangular Antiferromagnetic Phase in CsCu_<1-x>Co_xCl_3"Phys. Rev. B. 63. 224425-1-224425-6 (2001)
[Publications] A.Oosawa: "Field-Induced Neel Ordering in Spin gap Systems TlCuCl_3 and KCuCl_3"Physica B. 294-295. 34-38 (2001)
[Publications] S.Itoh: "Magnetic Correlations in CsVBr_3"J. Phys. Soc. Jpn. Suppl. A. 70. 169-171 (2001)
[Publications] A.Oosawa: "Neutron Inelastic Scattering from the Spin gap System TlCuCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 166-168 (2001)
[Publications] T.Ono: "Observation of the Oblique Triangular Antiferromagnetic Phase in CsCu_<1-x>Co_xCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 157-159 (2001)
[Publications] T.Kato: "Dispersion Curves of the Magnetic Excitation of KCuCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 160-162 (2001)
[Publications] H.Tanaka: "Field-Induced N6el Ordering and Bose-Einstein Condensation of Magnons in TlCuCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 163-165 (2001)
[Publications] S.Schmidt: "Phonon Effects and ESR in NH_4CuCl_3"Europhys. Lett.. 53. 591-597 (2001)
[Publications] S.Maruyama: "Susceptibility, Magnetization Process and ESR Studies on the Helical Spin System RbCuCl_3"J. Phys. Soc. Jpn.. 70. 859-865 (2001)
[Publications] A.Oosawa: "Specific Heat Study of the Field-Induced Magnetic Ordering in the Spin Gap System TlCuCl_3"Phys. Rev. B. 63. 134416-1-134416-4 (2001)
[Publications] H.Tanaka: "Observation of Field-Induced Transverse Neel Ordering in the Spin Gap System TlCuCl_3"J. Phys. Soc. Jpn.. 70. 939-942 (2001)
[Publications] M.Uchida: "Singlet Ground State and Magnetization Plateaus in Ba_3Mn_2O_8"J. Phys. Soc. Jpn.. 70. 1790-1793 (2001)
[Publications] R.Bugel: "CsMn(Br_xI_<1-x>)_3 : Crossover from an XY to an Ising Chiral Antiferromagnet"Phys. Rev. B. 64. 094406-1-094406-6 (2001)
[Publications] Y.Tanaka: "Field-Induced Two-Step Phase Transitions in the Singlet Ground State Triangular Antiferromagnet CsFeBr_3"J. Phys. Soc. Jpn.. 70. 3068-3075 (2001)
[Publications] A.Oosawa: "Magnetic Excitations and Exchange Interactions in the Spin gap System TlCuCl_3"Appl. Phys. A. (in press). (2002)
[Publications] T.Ono: "Spin Structure of CsCu_<1-x>Co_xCl_3 in the Magnetic Field"Appl. Phys. A. (in press). (2002)
[Publications] A.Oosawa: "Magnetic Excitations in the Spin gap System TlCuCl_3"Phys. Rev. B. 65. 094426-1-094426-7 (2002)
[Publications] S.Itoh: "Classical Properties in Spin Dynamics in the S=2 One-Dimensional Heisenberg Antiferromagnet, CsCrCl_3"J. Phys. Soc. Jpn.. 71(in press). (2002)
[Publications] H.Takeuchi: "EPR Study of Several Cr^<3+> Centers in K_2MgCl_4 Single Crystal"Proc. 3rd Asia-Pacific EPR/ESR Symposium. (in press). (2002)
[Publications] T.Ono: "ESR Measurements on Triangular Antiferromagnets CsCu_<1-x>Co_xCl_3"Proc. 3rd Asia-Pacific EPR/ESR Symposium. (in press). (2002)
[Publications] H.Tanaka: "Magnetic Phase Transition and Magnetization Plateau in Cs_2CuBr_4"Prog. Theor. Phys. Suppl.. (in press). (2002)
[Publications] O.Vyaselev: "Lattice Distortion and First Order Transition in TlCuCl_3"Proc. French-Lapanese Symposium on "Quantum Properties of Low-Dimensional Antiferromagnets". (2002)
[Publications] H.Tanaka: "Field-Induced Quantum magnetism in TlCuCl_3"Proc. French-Lapanese Symposium on "Quantum Properties of Low-Dimensional Antiferromagnets". (2002)
[Publications] 田中秀数: "TlCuCl_3の磁場誘起相転移とマグノンのボース・アインシュタイン凝縮"日本物理学会誌. 56. 110-114 (2001)
[Publications] I.Affleck: "Quantum brownian motion on a triangular lattice and c=2 boundary conformal field theory"Nucl. Phys. B. 594. 535-606 (2001)
[Publications] I.Affleck: "Boundary critical phenomena in SU(3) "spin" chain"J. Phys. A. 34. 1073-1088 (2001)
[Publications] M.Oshikawa: "Electron Spin Resonance in S=1/2 antiferromagnetic chains"Phys. Rev. B. (in press). (2002)
[Publications] 押川正毅: "スピンと磁性--スピンの量子性はいかに発現するか--"数理科学. 457・7. 29-36 (2001)
[Publications] K.Suzuki: "Pressure-induced metamagnetic behavior in a quasi -one-dimensional molecule-based ferrimagnet"Chem. Lett.. (in press). (2002)
[Publications] Y.Hosokoshi: "Approach to a single-component ferrimagnetism by organic radical crystals"J. Am. Chem. Soc.. 123. 7921-7922 (2001)
[Publications] M.Tanaka: "Magnetic properties of layered complexes [M(hfac)2]3・(R)2, M=Mn(II) and Cu(II), with trisnitroxide radicals having various metal-radical exchange interactions"J. Phys. Condens. Matter. 13. 7429-7442 (2001)
[Publications] S.Aonuma: "Structure and properties of novel M(dmit)2 salts with the Me3N-TEMPO radical (Me3N-TEMPO=N, N, N-trimethyl (1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl) ammonium)"J. Mater. Chem.. 11. 337-345 (2001)
[Publications] S.Hayami: "Pressure-stabilized low-spin state for binuclear iron(III) spin-crossover compounds"Bull. Chem. Soc. Jpn.. 74. 2361-2368 (2001)
[Publications] M.Tanaka: "Metal (3d)-organic (2p)-hybrid magnets made of Mn(II) ions with tris(aminoxyl) radicals (R's) as bridging ligands 2D complexes [{Mn(hfac)2}3_R2]"Synth Metals. 122. 463-470 (2001)
[Publications] K.Suzuki: "Pressure Effects on Molecular Magnets of Mn Complexes with Bisaminoxylbenzene Derivatives"Mol. Cryst. Liq. Cryst.. (in press). (2002)
[Publications] K.Katoh: "Magnetic properties of organic two-leg spin ladder systems with S=1/2 and S=1"J. Phys. Chem. Solids. (in press). (2002)
[Publications] N.Azuma: "Synthesis and magnetic property of the salts of positively charged verdazyl radicals and TCNQF4-anion radical"Mol. Cryst. Liq. Cryst.. (in press). (2002)
[Publications] M.Inokuchi: "Magnetic properties of Cs and N(CH3)4 salts of TCNQ"Mol. Cryst. Liq. Cryst.. (in press). (2002)
[Publications] S.Aonuma: "Structure and property of M(dmit)2 salt with trimethylammonio-TEMPO and related magnetic organic cations"Mol. Cryst. Liq. Cryst.. (in press). (2002)
[Publications] T.Goto: "Observation of a magnetization plateau of 1/4 in a novel double spin chain of ferromagnetic dimers formed by organic tetraradicals"Physica B. 294. 43-46 (2001)
[Publications] Y.Hosokoshi: "Magnetic properties of organic spin ladder systems"Synth. Metals. 121. 1838-1839 (2001)
[Publications] S.Aonuma: "Structure and properties of M(dmit)2 salts of cations with a magnetic nitroxide radical"Synth. Metals. 120. 993-994 (2001)
[Publications] K.Mukai: "Syntheses and properties of genuine organic magnetic conductors: (1 : 1) and (1 : 2) salts of ethyl-pyridinium-substituted verdazyl radicals with TCNQ"Polyhedron. 20. 1537-1544 (2001)
[Publications] H.Kumagai: "Synthesis, structure and magnetic properties of bis (hexafluoroacetylacetonato) Mn (II) complex with a novel triplet organic radical, 4-N-tert-butylarninoxyl-4' nitronylnitroxylbiphenyl"Polyhedron. 20. 1329-1333 (2001)
[Publications] N.V.Baranov: "Magnetic viscosity at the metamagnetic phase transition in organic MnII(hfac)2 compound with the one-dimensional chain structure"Mater. Sci. Forum. 373. 441-444 (2001)

2001 Fiscal Year Annual Research Report

磁場が誘起するマグノンのボース・アインシュタイン凝縮と局在

Principal Investigator

田中 秀数 東京工業大学, 大学院・理工学研究科, 助教授 (80188325)

Research Products

[Publications] M.Reehuis: "Partial Frustration of the Copper Spins in RbCuCl_3"J. Phys. Chem. Solids. 62. 1139-1143 (2001)

[Publications] B.Wolf: "Ultrasonic Experiments in SrCu_2(BO_3)_2, and NH_4CuCl_3 in Magnetic Fields up to 50T"J. Magn. & Magn. Mater.. 226. 1139-1143 (2001)

[Publications] K.Kakurai: "Neutron Scattering Experiments on Low-Dimensional Quantum Spin Systems -Spin Excitations in KCuCl_3 and SrCu_2(BO_3)_2 -"J. Phys. Chem. Solids. 62. 141-147 (2001)

[Publications] T.Ono: "Oblique Triangular Antiferromagnetic Phase in CsCu_<1-x>Co_xCl_3"Phys. Rev. B. 63. 224425-1-224425-6 (2001)

[Publications] A.Oosawa: "Field-Induced Neel Ordering in Spin gap Systems TlCuCl_3 and KCuCl_3"Physica B. 294-295. 34-38 (2001)

[Publications] S.Itoh: "Magnetic Correlations in CsVBr_3"J. Phys. Soc. Jpn. Suppl. A. 70. 169-171 (2001)

[Publications] A.Oosawa: "Neutron Inelastic Scattering from the Spin gap System TlCuCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 166-168 (2001)

[Publications] T.Ono: "Observation of the Oblique Triangular Antiferromagnetic Phase in CsCu_<1-x>Co_xCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 157-159 (2001)

[Publications] T.Kato: "Dispersion Curves of the Magnetic Excitation of KCuCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 160-162 (2001)

[Publications] H.Tanaka: "Field-Induced N6el Ordering and Bose-Einstein Condensation of Magnons in TlCuCl_3"J. Phys. Soc. Jpn. Suppl. A. 70. 163-165 (2001)

[Publications] S.Schmidt: "Phonon Effects and ESR in NH_4CuCl_3"Europhys. Lett.. 53. 591-597 (2001)

[Publications] S.Maruyama: "Susceptibility, Magnetization Process and ESR Studies on the Helical Spin System RbCuCl_3"J. Phys. Soc. Jpn.. 70. 859-865 (2001)

[Publications] A.Oosawa: "Specific Heat Study of the Field-Induced Magnetic Ordering in the Spin Gap System TlCuCl_3"Phys. Rev. B. 63. 134416-1-134416-4 (2001)

[Publications] H.Tanaka: "Observation of Field-Induced Transverse Neel Ordering in the Spin Gap System TlCuCl_3"J. Phys. Soc. Jpn.. 70. 939-942 (2001)

[Publications] M.Uchida: "Singlet Ground State and Magnetization Plateaus in Ba_3Mn_2O_8"J. Phys. Soc. Jpn.. 70. 1790-1793 (2001)

[Publications] R.Bugel: "CsMn(Br_xI_<1-x>)_3 : Crossover from an XY to an Ising Chiral Antiferromagnet"Phys. Rev. B. 64. 094406-1-094406-6 (2001)

[Publications] Y.Tanaka: "Field-Induced Two-Step Phase Transitions in the Singlet Ground State Triangular Antiferromagnet CsFeBr_3"J. Phys. Soc. Jpn.. 70. 3068-3075 (2001)

[Publications] A.Oosawa: "Magnetic Excitations and Exchange Interactions in the Spin gap System TlCuCl_3"Appl. Phys. A. (in press). (2002)

[Publications] T.Ono: "Spin Structure of CsCu_<1-x>Co_xCl_3 in the Magnetic Field"Appl. Phys. A. (in press). (2002)

[Publications] A.Oosawa: "Magnetic Excitations in the Spin gap System TlCuCl_3"Phys. Rev. B. 65. 094426-1-094426-7 (2002)

[Publications] S.Itoh: "Classical Properties in Spin Dynamics in the S=2 One-Dimensional Heisenberg Antiferromagnet, CsCrCl_3"J. Phys. Soc. Jpn.. 71(in press). (2002)

[Publications] H.Takeuchi: "EPR Study of Several Cr^<3+> Centers in K_2MgCl_4 Single Crystal"Proc. 3rd Asia-Pacific EPR/ESR Symposium. (in press). (2002)

[Publications] T.Ono: "ESR Measurements on Triangular Antiferromagnets CsCu_<1-x>Co_xCl_3"Proc. 3rd Asia-Pacific EPR/ESR Symposium. (in press). (2002)

[Publications] H.Tanaka: "Magnetic Phase Transition and Magnetization Plateau in Cs_2CuBr_4"Prog. Theor. Phys. Suppl.. (in press). (2002)

[Publications] O.Vyaselev: "Lattice Distortion and First Order Transition in TlCuCl_3"Proc. French-Lapanese Symposium on "Quantum Properties of Low-Dimensional Antiferromagnets". (2002)

[Publications] H.Tanaka: "Field-Induced Quantum magnetism in TlCuCl_3"Proc. French-Lapanese Symposium on "Quantum Properties of Low-Dimensional Antiferromagnets". (2002)

[Publications] 田中秀数: "TlCuCl_3の磁場誘起相転移とマグノンのボース・アインシュタイン凝縮"日本物理学会誌. 56. 110-114 (2001)

[Publications] I.Affleck: "Quantum brownian motion on a triangular lattice and c=2 boundary conformal field theory"Nucl. Phys. B. 594. 535-606 (2001)

[Publications] I.Affleck: "Boundary critical phenomena in SU(3) "spin" chain"J. Phys. A. 34. 1073-1088 (2001)

[Publications] M.Oshikawa: "Electron Spin Resonance in S=1/2 antiferromagnetic chains"Phys. Rev. B. (in press). (2002)

[Publications] 押川正毅: "スピンと磁性--スピンの量子性はいかに発現するか--"数理科学. 457・7. 29-36 (2001)

[Publications] K.Suzuki: "Pressure-induced metamagnetic behavior in a quasi -one-dimensional molecule-based ferrimagnet"Chem. Lett.. (in press). (2002)

[Publications] Y.Hosokoshi: "Approach to a single-component ferrimagnetism by organic radical crystals"J. Am. Chem. Soc.. 123. 7921-7922 (2001)

[Publications] M.Tanaka: "Magnetic properties of layered complexes [M(hfac)2]3・(R)2, M=Mn(II) and Cu(II), with trisnitroxide radicals having various metal-radical exchange interactions"J. Phys. Condens. Matter. 13. 7429-7442 (2001)

[Publications] S.Aonuma: "Structure and properties of novel M(dmit)2 salts with the Me3N-TEMPO radical (Me3N-TEMPO=N, N, N-trimethyl (1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl) ammonium)"J. Mater. Chem.. 11. 337-345 (2001)

[Publications] S.Hayami: "Pressure-stabilized low-spin state for binuclear iron(III) spin-crossover compounds"Bull. Chem. Soc. Jpn.. 74. 2361-2368 (2001)

[Publications] M.Tanaka: "Metal (3d)-organic (2p)-hybrid magnets made of Mn(II) ions with tris(aminoxyl) radicals (R's) as bridging ligands 2D complexes [{Mn(hfac)2}3_R2]"Synth Metals. 122. 463-470 (2001)

[Publications] K.Suzuki: "Pressure Effects on Molecular Magnets of Mn Complexes with Bisaminoxylbenzene Derivatives"Mol. Cryst. Liq. Cryst.. (in press). (2002)

[Publications] K.Katoh: "Magnetic properties of organic two-leg spin ladder systems with S=1/2 and S=1"J. Phys. Chem. Solids. (in press). (2002)

[Publications] N.Azuma: "Synthesis and magnetic property of the salts of positively charged verdazyl radicals and TCNQF4-anion radical"Mol. Cryst. Liq. Cryst.. (in press). (2002)

[Publications] M.Inokuchi: "Magnetic properties of Cs and N(CH3)4 salts of TCNQ"Mol. Cryst. Liq. Cryst.. (in press). (2002)

[Publications] S.Aonuma: "Structure and property of M(dmit)2 salt with trimethylammonio-TEMPO and related magnetic organic cations"Mol. Cryst. Liq. Cryst.. (in press). (2002)

[Publications] T.Goto: "Observation of a magnetization plateau of 1/4 in a novel double spin chain of ferromagnetic dimers formed by organic tetraradicals"Physica B. 294. 43-46 (2001)

[Publications] Y.Hosokoshi: "Magnetic properties of organic spin ladder systems"Synth. Metals. 121. 1838-1839 (2001)

[Publications] S.Aonuma: "Structure and properties of M(dmit)2 salts of cations with a magnetic nitroxide radical"Synth. Metals. 120. 993-994 (2001)

[Publications] K.Mukai: "Syntheses and properties of genuine organic magnetic conductors: (1 : 1) and (1 : 2) salts of ethyl-pyridinium-substituted verdazyl radicals with TCNQ"Polyhedron. 20. 1537-1544 (2001)

[Publications] H.Kumagai: "Synthesis, structure and magnetic properties of bis (hexafluoroacetylacetonato) Mn (II) complex with a novel triplet organic radical, 4-N-tert-butylarninoxyl-4' nitronylnitroxylbiphenyl"Polyhedron. 20. 1329-1333 (2001)

[Publications] N.V.Baranov: "Magnetic viscosity at the metamagnetic phase transition in organic MnII(hfac)2 compound with the one-dimensional chain structure"Mater. Sci. Forum. 373. 441-444 (2001)

田中秀数東京工業大学, 大学院・理工学研究科, 助教授 (80188325)