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題名 利用第一原理計算研究多鐵氧化物Cu3Mo2O9的磁性,電子態及鐵電性質
Ab Initio Studies of The Magnetic, Electronic and Ferroelectric Properties of Multiferroic Oxide Cu3Mo2O9作者 蕭逸修
Hsiao, Yi Hsiu貢獻者 郭光宇
Guo, Guang Yu
蕭逸修
Hsiao, Yi Hsiu關鍵詞 第一原理
多鐵氧化物
鐵電性
幾何不穩定性
Ab Initio
multiferroic oxide
ferroelectricity
geometric frustration日期 2012 上傳時間 30-Oct-2012 15:22:21 (UTC+8) 摘要 在此論文中,我們利用第一原理計算研究多鐵材料Cu3Mo2O9的磁性、電子態及多鐵性質。我們發現在此系統中,電子與電子間的庫倫排斥力必須被考慮,以致於導帶與價帶間能隙能夠被良好地描述。由於晶體結構所導致的幾何不穩定性,系統的磁結構尚未在實驗測量中被確定。在我們的理論計算當中得到的磁結構與Vilminot等研究人員根據實驗結果猜測出的非線性反鐵磁結構類似。交換作用與自旋軌道耦合間的爭競決定了電子自旋方向的傾斜。計算所得到的交換作用係數與實驗結果吻合良好。利用Berry’s phase計算,我們得到了系統自發電極化的理論值,其強度與實驗量測值在同一個數量級。然而,在我們計算中得到的電極化方向(平行於b軸)與實驗(平行於c軸)不符。此外,我們發現一磁結構之理論電極化方向與實驗相符,然而其磁結構之對稱性與實驗不符。目前,尚未有第一原理計算研究此氧化物,我們希望此論文能夠對同樣有興趣研究此材料的研究人員有所幫助。
In this thesis, we used the ab initio method to study a multiferroic oxide Cu3Mo2O9. The correlations of electrons must be considered in this system so that a reasonable energy gap can be obtained. Due to the geometric frustration of magnetic structure caused by crystal structure, the ground state spin configuration in this system still has not been determined experimentally. We found some spin configurations similar to the non-collinear anti-ferromagnetic spins configuration suggested by Vilminot et al.. Competition between exchange interactions and spin-orbit coupling effect determines the canting of spins on Cu atoms. The calculated exchange parameters agree with the experimental results well. By using Berry phase calculations, we obtained the theoretical value of spontaneous electric polarization. The strength of polarization in our results is in the same order of results of experiments. However, the direction of electric polarization we found (along b-axis) is different from the experimental measurements (along c-axis). We have found a spin configuration that the theoretical electric polarization of the state agrees with the experimental results. However, the symmetry of the spin configuration does not satisfy the conditions suggested by results of the neutron diffraction experiment. And, spins on neighboring Cu2 and Cu3 do not form a singlet dimer. Since there still is no ab initio calculation studying this oxide, we hope that our studies can help those who are also interested in this material.參考文獻 [1] P. Hohenberg andW. Kohn, ”Inhomogeneous Electron Gas”, Phys. Rev. 136, B864 (1964).[2] W. Kohn and L. J. Sham, ”Self-Consistent Equations Including Exchange and CorrelationEffects”, Phys. Rev. 140, A1133 (1965).[3] M. Born and J. R. Oppenheimer, ”On The Quantum Theory of Molecules”, Ann. Physik84, 457 (1927).[4] L. H. Thomas, ”The Calculation of Atomic Fields”, Proc. Camb. Phil. Soc. 23, 542 (1927).[5] J. P. Perdew and A. Zunger, ”Self-interaction correction to density-functional approximationsfor many-electron systems”, Phys. Rev. B 23, 5048 (1981).[6] J. P. Perdew, J. A. Chevary, S. H. Vosko, K. A. Jackson, M. R. Pederson, D. J. Singh, andC. Fiolhais, ”Atoms, Molecules, Solids, and Surfaces: Applications of The GeneralizedGradient Approximation for Exchange and Correlation”, Phys. Rev. B 46, 6671 (1992);48, 4978(E)(1993).[7] J. P. Perdew, K. Burke, and M. Ernzerhof, ”Generalized Gradient Approximation MadeSimple”, Phys. Rev. Lett. 77, 3865 (1996).[8] J. H. de Boer and E. J. W. Verwey, ”Semi-Conductors with Partially and with CompletelyFilled 3d-Lattice Bands”, Proc. Phys. Soc. 49, 59 (1937).[9] J. Hubbard, ”Electron Correlations in Narrow Energy Bands.”, Proc. Roy. Soc. A 276, 238(1963).[10] J. Hubbard, ”Electron Correlations in Narrow Energy Bands. III. An Improved Solution”,Proc. Roy. Soc. A 281, 41 (1964).[11] A. Svane and O. Gunnarsson, ”Transition-Metal Oxides in The Self-Interaction-CorrectedDensity-Functional Formalism”, Phys. Rev. Lett. 65, 1148 (1990).[12] S. Massidda, M. Posternak and A. Baldereschi, ”Hartree-Fock LAPW Approach to TheElectronic Properties of Periodic Systems”, Phys. Rev. B 48, 5058 (1993).[13] L. Hedin, ”New Method for Calculating The One-Particle Green’s Function with Applicationto the Electron-Gas Problem”, Phys. Rev. 139, A796 (1965).[14] A. I. Liechtenstein, V. I. Anisimov and J. Zaanen, ”Density-Functional Theory and StrongInteractions: Orbital Ordering in Mott-Hubbard Insulators”, Phys. Rev. B 52, R5467(1995).[15] S. L. Dudarev, G. A. Botton, S. Y. Savrasov, C. J. Humphreys and A. P. Sutton, ”Electron-Energy-Loss Spectra and The Structural Stability of Nickel Oxide:An LSDA+U Study”,Phys. Rev. B 57, 1505 (1998).[16] H. Bethe, ”Splitting of Terms in Crystals”, Ann. Physik 3, 133 (1929).[17] J. H. Van Vleck, ”Theory of The Variations in Paramagnetic Anisotropy Among DifferentSalts of The Iron Group”, Phys. Rev. 41, 208 (1932).[18] H. A. Jahn and E. Teller, ”Stability of polyatomic Molecules in Degenerate ElectronicStates. I. Orbital Degeneracy”, Proc. Roy. Soc. A 161, 220 (1937).[19] J. Springborg and C. E. Schaffer, ”Tetrakis (pyridine) Cobalt(III) Complexes”, Acta. Chem.Scand. 27, 3312 (1973).[20] L. D. Landau and E. M. Lifshitz, Electrodynamics of continuous media (Fizmatgiz,Moscow, 1959).[21] E. Ascher, H. Rieder, H. Schmid and H. Stossel, ”Some Properteis of FerromagnetoelectricNickel-Iodine Boracite, Ni3B7O13I”, J. Appl. Phys. 37, 1404 (1966).[22] J. Wang, J. B. Neaton, H. Zheng, V. Nagarajan, S. B. Ogale, B. Liu, D. Viehland, V.Vaithyanathan, D. G. Schlom, U. V. Waghmare, N. A. Spaldin, K. M. Rabe, M. Wuttigand R. Ramesh, ”Epitaxial BiFeO3 Multiferroic Thin Film Heterostructures”, Science 299,1719 (2003).[23] N. Hur, S. Park, P. A. Sharma, J. S. Ahn, S. Guha and S-W. Cheong, ”Electric PolarizationReversal and Memory in A Multiferroic Material Induced by Magnetic Fields”, Nature429, 392 (2004).[24] T. Kimura, T. Goto, H. Shintani, K. Ishizaka, T. Arima and Y. Tokura, ”Magnetic Controlof Ferroelectric Polarization”, Nature 426, 55 (2003).[25] G. Toulouse, ”Theory of The Frustration Effect in Spin Glasses I”, Commun. Phys. 2, 115(1977).[26] J. Vannimenus and G. Toulouse, ”Theory of The Frustration Effect. II. Ising Spins on ASquare Lattice”, J. Phys. C: Solid State Phys. 10, L537 (1977).[27] G. H. Wannier, ”Antiferromagnetism. The Triangular Ising Net”, Phys. Rev. 79, 357(1950).[28] L. Pauling, ”The Structure and Entropy of Ice and of Other Crystals with Some Randomnessof Atomic Arrangement”, J. Am. Chem. Soc. 57 2680 (1935).[29] N. A. Hill, ”Why Are There so Few Magnetic Ferroelectrics?”, J. Phys. Chem. B 104, 6694(2000).[30] D. I. Khomskii, ”Multiferroics: Different Ways to Combine Magnetism and Ferroelectricity”,J. Magn. Magn. Mater. 306, 1 (2006).[31] D. V. Efremov, J. van den Brink, and D. I. Khomskii, ”Bond-Versus Site-Centred Orderingand Possible Ferroelectricity in Manganites”, Nature Mater. 3, 853 (2004).[32] B. B. Van Aken, T. T. M. Palstra, A. Filippetti and N. A. Spaldin, ”The Origin of Ferroelectricityin Magnetoelectric YMnO3”, Nature Mater. 3, 164 (2004).[33] D. Khomskii, ”Classifying Multiferroics: Mechanisms and Effects”, Physics 2, 20 (2009).[34] H. Katsura, N. Nagaosa and A. V. Balatsky, ”Spin Current and Magnetoelectric Effect inNoncollinear Magnets”, Phys. Rev. Lett. 95, 057205 (2005).[35] M. V. Mostovoy, ”Ferroelectricity in Spiral Magnets”, Phys. Rev. Lett. 96, 067601 (2006).[36] M. Fiebig, ”Revival of The Magnetoelectric Effect”, J. Phys. D 38, R123 (2005).[37] H. Kuroe, T. Hosaka, S. Hachiuma, T. Sekine, M. Hase, K. Oka, T. Ito, H. Eisaki, M.Fujisawa, S. Okubo and H. Ohta, ”Electric Polarization Induced by Neel Order withoutMagnetic Superlattice: Experimental Study of Cu3Mo2O9 and Numerical Study of A SmallSpin Cluster”, J. Phys. Soc. Jpn. 80, 083705 (2011).[38] S. Vilminot, G. Andre and M. Kurmoo, ”Magnetic Properties and Magnetic Structure ofCu3Mo2O9”, Inorg. Chem, 48, 2687 (2009).[39] T. Hamasaki, T. Ide, H. Kuroe and T. Sekine, ”Successive Phase Transitions to Antiferromagneticand Weak-Ferromagnetic Long-Range Order in The Quasi-One-DimensionalAntiferromagnet Cu3Mo2O9”, Phys. Rev. B 77, 134419 (2008). 描述 碩士
國立政治大學
應用物理研究所
99755007
101資料來源 http://thesis.lib.nccu.edu.tw/record/#G0099755007 資料類型 thesis dc.contributor.advisor 郭光宇 zh_TW dc.contributor.advisor Guo, Guang Yu en_US dc.contributor.author (Authors) 蕭逸修 zh_TW dc.contributor.author (Authors) Hsiao, Yi Hsiu en_US dc.creator (作者) 蕭逸修 zh_TW dc.creator (作者) Hsiao, Yi Hsiu en_US dc.date (日期) 2012 en_US dc.date.accessioned 30-Oct-2012 15:22:21 (UTC+8) - dc.date.available 30-Oct-2012 15:22:21 (UTC+8) - dc.date.issued (上傳時間) 30-Oct-2012 15:22:21 (UTC+8) - dc.identifier (Other Identifiers) G0099755007 en_US dc.identifier.uri (URI) http://nccur.lib.nccu.edu.tw/handle/140.119/55038 - dc.description (描述) 碩士 zh_TW dc.description (描述) 國立政治大學 zh_TW dc.description (描述) 應用物理研究所 zh_TW dc.description (描述) 99755007 zh_TW dc.description (描述) 101 zh_TW dc.description.abstract (摘要) 在此論文中,我們利用第一原理計算研究多鐵材料Cu3Mo2O9的磁性、電子態及多鐵性質。我們發現在此系統中,電子與電子間的庫倫排斥力必須被考慮,以致於導帶與價帶間能隙能夠被良好地描述。由於晶體結構所導致的幾何不穩定性,系統的磁結構尚未在實驗測量中被確定。在我們的理論計算當中得到的磁結構與Vilminot等研究人員根據實驗結果猜測出的非線性反鐵磁結構類似。交換作用與自旋軌道耦合間的爭競決定了電子自旋方向的傾斜。計算所得到的交換作用係數與實驗結果吻合良好。利用Berry’s phase計算,我們得到了系統自發電極化的理論值,其強度與實驗量測值在同一個數量級。然而,在我們計算中得到的電極化方向(平行於b軸)與實驗(平行於c軸)不符。此外,我們發現一磁結構之理論電極化方向與實驗相符,然而其磁結構之對稱性與實驗不符。目前,尚未有第一原理計算研究此氧化物,我們希望此論文能夠對同樣有興趣研究此材料的研究人員有所幫助。 zh_TW dc.description.abstract (摘要) In this thesis, we used the ab initio method to study a multiferroic oxide Cu3Mo2O9. The correlations of electrons must be considered in this system so that a reasonable energy gap can be obtained. Due to the geometric frustration of magnetic structure caused by crystal structure, the ground state spin configuration in this system still has not been determined experimentally. We found some spin configurations similar to the non-collinear anti-ferromagnetic spins configuration suggested by Vilminot et al.. Competition between exchange interactions and spin-orbit coupling effect determines the canting of spins on Cu atoms. The calculated exchange parameters agree with the experimental results well. By using Berry phase calculations, we obtained the theoretical value of spontaneous electric polarization. The strength of polarization in our results is in the same order of results of experiments. However, the direction of electric polarization we found (along b-axis) is different from the experimental measurements (along c-axis). We have found a spin configuration that the theoretical electric polarization of the state agrees with the experimental results. However, the symmetry of the spin configuration does not satisfy the conditions suggested by results of the neutron diffraction experiment. And, spins on neighboring Cu2 and Cu3 do not form a singlet dimer. Since there still is no ab initio calculation studying this oxide, we hope that our studies can help those who are also interested in this material. en_US dc.description.tableofcontents List of Figures . . . . . . . . . . . . . . . . . . 3List of Tables. . . . . . . . . . . . . . . . . . . 71 Introduction 82 Density Functional Theory 92.1 Born-Oppenheimer approximation . . . . . . . . 92.2 Thomas-Fermi Theory. . . . . . . . . . . . . . 102.3 Density Functional Theory. . . . . . . . . . . 112.3.1 Hohenberg-Kohn Theorem . . . . . . . . . . . 122.3.2 Kohn-Sham Equation . . . . . . . . . . . . . 132.3.3 Exchange-Correlation Energy. . . . . . . . . 142.4 Mott Insulators. . . . . . . . . . . . . . . . 152.4.1 Hubbard Model. . . . . . . . . . . . . . . . 152.4.2 Beyond DFT : DFT+U . . . . . . . . . . . . . 173 Crystal Field Theory 183.1 Atomic Orbitals. . . . . . . . . . . . . . . . 183.2 Crystal Field Theory . . . . . . . . . . . . . 193.3 High Spin and Low Spin . . . . . . . . . . . . 213.4 Crystal Field Stabilization Energy . . . . . . 223.5 Jahn-Teller Theorem. . . . . . . . . . . . . . 233.6 Colors of Transition Metal Complexes . . . . . 234 Multiferroics 254.1 Introduction . . . . . . . . . . . . . . . . . 254.2 Symmetry . . . . . . . . . . . . . . . . . . . 264.3 Geometric Frustration. . . . . . . . . . . . . 274.4 Multiferroics. . . . . . . . . . . . . . . . . 274.4.1 Type-I Multiferroics . . . . . . . . . . . . 274.4.2 Type-II Multiferroics. . . . . . . . . . . . 305 Calculated Physical Properties of Cu3Mo2O9 . . . 335.1 Introduction . . . . . . . . . . . . . . . . . 335.2 Crystal Structure and Computational Details. . 365.3 Magnetic Structure . . . . . . . . . . . . . . 405.4 Exchange Interactions. . . . . . . . . . . . . 405.5 Electronic Structure . . . . . . . . . . . . . 495.6 Spontaneous Electric Polarization. . . . . . . 586 Summary and Conclusions 61Reference. . . . . . . . . . . . . . . . . . . . . 66 zh_TW dc.language.iso en_US - dc.source.uri (資料來源) http://thesis.lib.nccu.edu.tw/record/#G0099755007 en_US dc.subject (關鍵詞) 第一原理 zh_TW dc.subject (關鍵詞) 多鐵氧化物 zh_TW dc.subject (關鍵詞) 鐵電性 zh_TW dc.subject (關鍵詞) 幾何不穩定性 zh_TW dc.subject (關鍵詞) Ab Initio en_US dc.subject (關鍵詞) multiferroic oxide en_US dc.subject (關鍵詞) ferroelectricity en_US dc.subject (關鍵詞) geometric frustration en_US dc.title (題名) 利用第一原理計算研究多鐵氧化物Cu3Mo2O9的磁性,電子態及鐵電性質 zh_TW dc.title (題名) Ab Initio Studies of The Magnetic, Electronic and Ferroelectric Properties of Multiferroic Oxide Cu3Mo2O9 en_US dc.type (資料類型) thesis en dc.relation.reference (參考文獻) [1] P. Hohenberg andW. Kohn, ”Inhomogeneous Electron Gas”, Phys. Rev. 136, B864 (1964).[2] W. Kohn and L. J. Sham, ”Self-Consistent Equations Including Exchange and CorrelationEffects”, Phys. Rev. 140, A1133 (1965).[3] M. Born and J. R. Oppenheimer, ”On The Quantum Theory of Molecules”, Ann. Physik84, 457 (1927).[4] L. H. Thomas, ”The Calculation of Atomic Fields”, Proc. Camb. Phil. Soc. 23, 542 (1927).[5] J. P. Perdew and A. Zunger, ”Self-interaction correction to density-functional approximationsfor many-electron systems”, Phys. Rev. B 23, 5048 (1981).[6] J. P. Perdew, J. A. Chevary, S. H. Vosko, K. A. Jackson, M. R. Pederson, D. J. Singh, andC. Fiolhais, ”Atoms, Molecules, Solids, and Surfaces: Applications of The GeneralizedGradient Approximation for Exchange and Correlation”, Phys. Rev. B 46, 6671 (1992);48, 4978(E)(1993).[7] J. P. Perdew, K. Burke, and M. Ernzerhof, ”Generalized Gradient Approximation MadeSimple”, Phys. Rev. Lett. 77, 3865 (1996).[8] J. H. de Boer and E. J. W. Verwey, ”Semi-Conductors with Partially and with CompletelyFilled 3d-Lattice Bands”, Proc. Phys. Soc. 49, 59 (1937).[9] J. Hubbard, ”Electron Correlations in Narrow Energy Bands.”, Proc. Roy. Soc. A 276, 238(1963).[10] J. Hubbard, ”Electron Correlations in Narrow Energy Bands. III. An Improved Solution”,Proc. Roy. Soc. A 281, 41 (1964).[11] A. Svane and O. Gunnarsson, ”Transition-Metal Oxides in The Self-Interaction-CorrectedDensity-Functional Formalism”, Phys. Rev. Lett. 65, 1148 (1990).[12] S. Massidda, M. Posternak and A. Baldereschi, ”Hartree-Fock LAPW Approach to TheElectronic Properties of Periodic Systems”, Phys. Rev. B 48, 5058 (1993).[13] L. Hedin, ”New Method for Calculating The One-Particle Green’s Function with Applicationto the Electron-Gas Problem”, Phys. Rev. 139, A796 (1965).[14] A. I. Liechtenstein, V. I. Anisimov and J. Zaanen, ”Density-Functional Theory and StrongInteractions: Orbital Ordering in Mott-Hubbard Insulators”, Phys. Rev. B 52, R5467(1995).[15] S. L. Dudarev, G. A. Botton, S. Y. Savrasov, C. J. Humphreys and A. P. Sutton, ”Electron-Energy-Loss Spectra and The Structural Stability of Nickel Oxide:An LSDA+U Study”,Phys. Rev. B 57, 1505 (1998).[16] H. Bethe, ”Splitting of Terms in Crystals”, Ann. Physik 3, 133 (1929).[17] J. H. Van Vleck, ”Theory of The Variations in Paramagnetic Anisotropy Among DifferentSalts of The Iron Group”, Phys. Rev. 41, 208 (1932).[18] H. A. Jahn and E. Teller, ”Stability of polyatomic Molecules in Degenerate ElectronicStates. I. Orbital Degeneracy”, Proc. Roy. Soc. A 161, 220 (1937).[19] J. Springborg and C. E. Schaffer, ”Tetrakis (pyridine) Cobalt(III) Complexes”, Acta. Chem.Scand. 27, 3312 (1973).[20] L. D. Landau and E. M. Lifshitz, Electrodynamics of continuous media (Fizmatgiz,Moscow, 1959).[21] E. Ascher, H. Rieder, H. Schmid and H. Stossel, ”Some Properteis of FerromagnetoelectricNickel-Iodine Boracite, Ni3B7O13I”, J. Appl. Phys. 37, 1404 (1966).[22] J. Wang, J. B. Neaton, H. Zheng, V. Nagarajan, S. B. Ogale, B. Liu, D. Viehland, V.Vaithyanathan, D. G. Schlom, U. V. Waghmare, N. A. Spaldin, K. M. Rabe, M. Wuttigand R. Ramesh, ”Epitaxial BiFeO3 Multiferroic Thin Film Heterostructures”, Science 299,1719 (2003).[23] N. Hur, S. Park, P. A. Sharma, J. S. Ahn, S. Guha and S-W. Cheong, ”Electric PolarizationReversal and Memory in A Multiferroic Material Induced by Magnetic Fields”, Nature429, 392 (2004).[24] T. Kimura, T. Goto, H. Shintani, K. Ishizaka, T. Arima and Y. Tokura, ”Magnetic Controlof Ferroelectric Polarization”, Nature 426, 55 (2003).[25] G. Toulouse, ”Theory of The Frustration Effect in Spin Glasses I”, Commun. Phys. 2, 115(1977).[26] J. Vannimenus and G. Toulouse, ”Theory of The Frustration Effect. II. Ising Spins on ASquare Lattice”, J. Phys. C: Solid State Phys. 10, L537 (1977).[27] G. H. Wannier, ”Antiferromagnetism. The Triangular Ising Net”, Phys. Rev. 79, 357(1950).[28] L. Pauling, ”The Structure and Entropy of Ice and of Other Crystals with Some Randomnessof Atomic Arrangement”, J. Am. Chem. Soc. 57 2680 (1935).[29] N. A. Hill, ”Why Are There so Few Magnetic Ferroelectrics?”, J. Phys. Chem. B 104, 6694(2000).[30] D. I. Khomskii, ”Multiferroics: Different Ways to Combine Magnetism and Ferroelectricity”,J. Magn. Magn. Mater. 306, 1 (2006).[31] D. V. Efremov, J. van den Brink, and D. I. Khomskii, ”Bond-Versus Site-Centred Orderingand Possible Ferroelectricity in Manganites”, Nature Mater. 3, 853 (2004).[32] B. B. Van Aken, T. T. M. Palstra, A. Filippetti and N. A. Spaldin, ”The Origin of Ferroelectricityin Magnetoelectric YMnO3”, Nature Mater. 3, 164 (2004).[33] D. Khomskii, ”Classifying Multiferroics: Mechanisms and Effects”, Physics 2, 20 (2009).[34] H. Katsura, N. Nagaosa and A. V. Balatsky, ”Spin Current and Magnetoelectric Effect inNoncollinear Magnets”, Phys. Rev. Lett. 95, 057205 (2005).[35] M. V. Mostovoy, ”Ferroelectricity in Spiral Magnets”, Phys. Rev. Lett. 96, 067601 (2006).[36] M. Fiebig, ”Revival of The Magnetoelectric Effect”, J. Phys. D 38, R123 (2005).[37] H. Kuroe, T. Hosaka, S. Hachiuma, T. Sekine, M. Hase, K. Oka, T. Ito, H. Eisaki, M.Fujisawa, S. Okubo and H. Ohta, ”Electric Polarization Induced by Neel Order withoutMagnetic Superlattice: Experimental Study of Cu3Mo2O9 and Numerical Study of A SmallSpin Cluster”, J. Phys. Soc. Jpn. 80, 083705 (2011).[38] S. Vilminot, G. Andre and M. Kurmoo, ”Magnetic Properties and Magnetic Structure ofCu3Mo2O9”, Inorg. Chem, 48, 2687 (2009).[39] T. Hamasaki, T. Ide, H. Kuroe and T. Sekine, ”Successive Phase Transitions to Antiferromagneticand Weak-Ferromagnetic Long-Range Order in The Quasi-One-DimensionalAntiferromagnet Cu3Mo2O9”, Phys. Rev. B 77, 134419 (2008). zh_TW