2003 Fiscal Year Annual Research Report

量子コンピュータの量子ビット素子としての分子磁性体の設計

Research Project

Project/Area Number	15750120
Research Institution	Osaka University
Principal Investigator	川上貴資大阪大学, 大学院・理学研究科, 助手 (30321748)
Keywords	量子コンピュータ / 量子ドット素子 / 分子磁性 / 有機強磁性体 / 有機超伝導体 / 有機磁性金属 / 磁気的相互作用 / 有効交換積分
Research Abstract	量子コンピュータは、ごく近年にセンセーションを巻き起こしている。一方、分子磁性体は、我国にて世界に先駆けて発見された化学の重要な領域の一つである。そして、これらの融合として、量子コンピュータを分子磁性体にて実現することが考えられる。本研究では、「量子コンピュータの量子ビット素子としての分子磁性体の設計」を目指す。その実現のためには詳細な理論的議論が必要である。平成15年度はでは、分子軌道法を中心とした理論計算を駆使して、量子ビット素子に求められる条件を解析した。つまり、理論計算による量子ビット素子を分子磁性体にて構築するための理論展開に重点を置き、かつ実行するための計算手法の確立を行う。また、それに伴うプログラム開発も実行した。直接量子ビット素子の探索を行うのは非常に困難であるため、着実にアプローチするために、分子磁性体の分野での有機強磁性結晶及び分子性(超)伝導性結晶に関して、磁性スピン・遍歴電子の振る舞いを理論的に解析することを押し進めた。これら分子磁性体での磁気スピンが安定に存在する条件と、そのスピン源間の磁気的相互作用の発現メカニズムの解明は、量子ビットの設計にそのまま展開可能であった。つまり、量子ビット素子としては磁気スピンを採用することができ、量子コンピュータでの演算操作をそのスピン間の磁気的相互作用と読み替えることができることを示した。

Research Products

(20 results)

All Other

All Publications (20 results)

[Publications] T.Kawakami, et al.(1st author: "Theoretical determination of all the effective parameters in the BETS related crystals by HF and DFT methods."Synthetic Metals. 133-134. 565-567 (2003)
[Publications] T.Kawakami, et al.(1): "Theoretical analysis of magnetic parameters between donors in BEDT-TTF, BETS, TMTTF and TMTSF crystals."Synthetic Metals. 137. 1259-1260 (2003)
[Publications] T.Kawakami, et al.(1): "Theoretical studies of magnetic interactions in many types of organic donor salts : BEDT-TTF, BETS, TMTTF AND TMTSF."Polyhedron. 22. 2051-2065 (2003)
[Publications] Y.Yamashita, et al.(2): "Theoretical studies on effective parameters for ionic radical clusters : possibility of organic magnetic metals."Synthetic Metals. 133-134. 589-591 (2003)
[Publications] T.Taniguchi, et al.(2): "Theoretical studies of intra-and intermolecular magnetic interactions of organic polydradicals with S=1,2/3 and 2 spin sites."Synthetic Metals. 133-134. 585-587 (2003)
[Publications] K.Yamaguchi, et al.(2): "Theoretical studies on molecule-based magnetic conductors."Polyhedron. 22. 2077-2090 (2003)
[Publications] T.Taniguchi, et al.(3): "Theoretical study on model clusters for pure organomagnetic conductors."Synthetic Metals. 137. 1261-1262 (2003)
[Publications] S.Nakano, et al.(3): "Theoretical studies on electronic states of Rh-C60."Synthetic Metals. 135-136. 779-780 (2003)
[Publications] Y.Kitagawa, et al.(3): "Magnetic effective density functional studies on electronic states of Cr2(pyphos)4 and Pt2Cr2(pyphos)4(CH3)4."Polyhedron. 22. 2019-2025 (2003)
[Publications] S.Nakano, et al.(3): "Hybrid DFT study of electronic structure on quasi-one-dimensional halogen-bridged binuclear metal complexes(MMX)."Polyhedron. 22. 2027-2038 (2003)
[Publications] T.Taniguchi, et al.(3): "Theoretical study on pure organomagnetic conductors with model clusters."Polyhedron. 22. 2039-2043 (2003)
[Publications] M.Shoji, et al.(3): "Hybrid density-functional theory stodies on stable polycarbenes."Polyhedron. 22. 2067-2076 (2003)
[Publications] S.Yamanaka, et al.(3): "Spin correlation functions by generalized spin orbital density functional and multireference approaches."Int.J.Quant.Chem. 95. 512-520 (2003)
[Publications] S.Yamanaka et al.(3): "Ab initio density functional approach for noncollinear molecular magnetism of multicenter metal clusters."(in press.).
[Publications] R.Takeda, et al.(4): "Theoreticai studies on contributions of SOMO-SOMO and other couplings to the magnetic interaction in radical clusters."Synthetic Metals. 133-134. 593-595 (2003)
[Publications] H.Isobe, et al.(4): "Systematic comparisons between broken symmetry and symmetry-adapted approaches to transition states by chemical indices : A case study of the Diels-Alder reactions."J.Phys.Chem.A. 107. 682-694 (2003)
[Publications] K.Yamaguchi, et al.(5): "N-band Hubbard models II. Cooperative mechanisms of electron-phonon, electron correlation and many-band effects toward high-Tc superconductors."Int.J.Quant.Chem. 92. 47-70 (2003)
[Publications] T.Matsumoto, et al.(6): "Synthesis, crystal structure and magnetic properties of dimethylthiotetrathiafulvalenoquinone-1,3-dithiolemethide/CuBr42-salt incorporating neutral copper bromide arrays."Synthetic Metals. 135-136. 575-576 (2003)
[Publications] K.Yamaguchi, et al.(6): "Spin and pseudo spins in theoretical chemistry. A unified view for superposed and entangled quantum systems."Bull.Korean Chem.Soc.. 24(発表予定). (2003)
[Publications] T.Matsumoto, et al.(7): "One-dimensional CuBr42-ion array and CuBr3-ion chain included in the p conducting framework composed of bis(methylthio)tetrathiafulvalenothioquinone-1,3-dithiocarbonatodithiolemethide Molecules."Inorg.Chem.. 42. 8638-8645 (2003)

2003 Fiscal Year Annual Research Report

量子コンピュータの量子ビット素子としての分子磁性体の設計

Principal Investigator

川上 貴資 大阪大学, 大学院・理学研究科, 助手 (30321748)

Research Products

[Publications] T.Kawakami, et al.(1st author: "Theoretical determination of all the effective parameters in the BETS related crystals by HF and DFT methods."Synthetic Metals. 133-134. 565-567 (2003)

[Publications] T.Kawakami, et al.(1): "Theoretical analysis of magnetic parameters between donors in BEDT-TTF, BETS, TMTTF and TMTSF crystals."Synthetic Metals. 137. 1259-1260 (2003)

[Publications] T.Kawakami, et al.(1): "Theoretical studies of magnetic interactions in many types of organic donor salts : BEDT-TTF, BETS, TMTTF AND TMTSF."Polyhedron. 22. 2051-2065 (2003)

[Publications] Y.Yamashita, et al.(2): "Theoretical studies on effective parameters for ionic radical clusters : possibility of organic magnetic metals."Synthetic Metals. 133-134. 589-591 (2003)

[Publications] T.Taniguchi, et al.(2): "Theoretical studies of intra-and intermolecular magnetic interactions of organic polydradicals with S=1,2/3 and 2 spin sites."Synthetic Metals. 133-134. 585-587 (2003)

[Publications] K.Yamaguchi, et al.(2): "Theoretical studies on molecule-based magnetic conductors."Polyhedron. 22. 2077-2090 (2003)

[Publications] T.Taniguchi, et al.(3): "Theoretical study on model clusters for pure organomagnetic conductors."Synthetic Metals. 137. 1261-1262 (2003)

[Publications] S.Nakano, et al.(3): "Theoretical studies on electronic states of Rh-C60."Synthetic Metals. 135-136. 779-780 (2003)

[Publications] Y.Kitagawa, et al.(3): "Magnetic effective density functional studies on electronic states of Cr2(pyphos)4 and Pt2Cr2(pyphos)4(CH3)4."Polyhedron. 22. 2019-2025 (2003)

[Publications] S.Nakano, et al.(3): "Hybrid DFT study of electronic structure on quasi-one-dimensional halogen-bridged binuclear metal complexes(MMX)."Polyhedron. 22. 2027-2038 (2003)

[Publications] T.Taniguchi, et al.(3): "Theoretical study on pure organomagnetic conductors with model clusters."Polyhedron. 22. 2039-2043 (2003)

[Publications] M.Shoji, et al.(3): "Hybrid density-functional theory stodies on stable polycarbenes."Polyhedron. 22. 2067-2076 (2003)

[Publications] S.Yamanaka, et al.(3): "Spin correlation functions by generalized spin orbital density functional and multireference approaches."Int.J.Quant.Chem. 95. 512-520 (2003)

[Publications] S.Yamanaka et al.(3): "Ab initio density functional approach for noncollinear molecular magnetism of multicenter metal clusters."(in press.).

[Publications] R.Takeda, et al.(4): "Theoreticai studies on contributions of SOMO-SOMO and other couplings to the magnetic interaction in radical clusters."Synthetic Metals. 133-134. 593-595 (2003)

[Publications] H.Isobe, et al.(4): "Systematic comparisons between broken symmetry and symmetry-adapted approaches to transition states by chemical indices : A case study of the Diels-Alder reactions."J.Phys.Chem.A. 107. 682-694 (2003)

[Publications] K.Yamaguchi, et al.(5): "N-band Hubbard models II. Cooperative mechanisms of electron-phonon, electron correlation and many-band effects toward high-Tc superconductors."Int.J.Quant.Chem. 92. 47-70 (2003)

[Publications] T.Matsumoto, et al.(6): "Synthesis, crystal structure and magnetic properties of dimethylthiotetrathiafulvalenoquinone-1,3-dithiolemethide/CuBr42-salt incorporating neutral copper bromide arrays."Synthetic Metals. 135-136. 575-576 (2003)

[Publications] K.Yamaguchi, et al.(6): "Spin and pseudo spins in theoretical chemistry. A unified view for superposed and entangled quantum systems."Bull.Korean Chem.Soc.. 24(発表予定). (2003)

[Publications] T.Matsumoto, et al.(7): "One-dimensional CuBr42-ion array and CuBr3-ion chain included in the p conducting framework composed of bis(methylthio)tetrathiafulvalenothioquinone-1,3-dithiocarbonatodithiolemethide Molecules."Inorg.Chem.. 42. 8638-8645 (2003)

川上貴資大阪大学, 大学院・理学研究科, 助手 (30321748)