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Magnetism and its microscopic origin in iron-based high-temperature superconductors

Abstract

High-temperature superconductivity in the iron-based materials emerges from, or sometimes coexists with, their metallic or insulating parent compound states. This is surprising, as these undoped states exhibit dramatically different antiferromagnetic spin arrangements and Néel temperatures. Although there is a general consensus that magnetic interactions are important for superconductivity, much remains unknown concerning the microscopic origin of the magnetic states. In this review, we summarize the progress in this area, focusing on recent experimental and theoretical results, and their microscopic implications. We conclude that the parent compounds are in a state that is more complex than that implied by a simple Fermi surface nesting scenario, and a dual description including both itinerant and localized degrees of freedom is needed to properly describe these fascinating materials.

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Figure 1: AF structure and spin-wave dispersions for the insulating copper oxide La2CuO4 and the parent compounds of iron-based superconductors BaFe2As2, FeTe and AyFe1.6+xSe2.
Figure 2: The electronic phase diagrams and the evolution of FSs, static AF order and spin excitations on electron or hole doping to BaFe2As2.
Figure 3: Summary of the phase diagram of multiorbital Hubbard models and the electronic state of Fe near the FS.
Figure 4: Sketch of the expected phase diagram of the Hubbard model with varying temperature and U/W in the undoped limit.

References

  1. Bednorz, J. G. & Müller, K. A. Possible high-Tc superconductivity in the Ba–La–Cu–O system. Z. Phys. B 64, 189–193 (1986).

    Article  ADS  Google Scholar 

  2. Vaknin, D. et al. Antiferromagnetism in La2CuO4−y . Phys. Rev. Lett. 58, 2802–2805 (1987).

    ADS  Google Scholar 

  3. Tranquada, J. M. et al. Neutron-diffraction determination of antiferromagnetic structure of Cu ions in YBa2Cu3O6+x with x = 0.0 and 0.15. Phys. Rev. Lett. 60, 156–159 (1988).

    ADS  Google Scholar 

  4. Scalapino, D. J. The case for d x 2 − y 2 pairing in the cuprate superconductors. Phys. Rep. 250, 329–365 (1995).

    ADS  Google Scholar 

  5. Dagotto, E. Correlated electrons in high-temperature superconductors. Rev. Mod. Phys. 66, 763–840 (1994).

    ADS  Google Scholar 

  6. Lee, P. A., Nagaosa, N. & Wen, X-G. Doping a Mott insulator: Physics of high-temperature superconductivity. Rev. Mod. Phys. 78, 17–85 (2006).

    Article  ADS  Google Scholar 

  7. Fujita, M. et al. Progress in neutron scattering studies of spin excitations in high-Tc cuprates. J. Phys. Soc. Jpn 81, 011007 (2012).

    ADS  Google Scholar 

  8. Johnston, D. C. The puzzle of high temperature superconductivity in layered iron pnictides and chalcogenides. Adv. Phys. 59, 803–1061 (2010).

    ADS  Google Scholar 

  9. Stewart, G. R. Superconductivity in iron compounds. Rev. Mod. Phys. 83, 1589–1652 (2011).

    ADS  Google Scholar 

  10. Paglione, J. & Greene, R. L. High-temperature superconductivity in iron-based materials. Nature Phys. 6, 645–658 (2010).

    ADS  Google Scholar 

  11. Kamihara, Y., Watanabe, T., Hirano, M. & Hosono, H. Iron-based layered superconductor La[O1−xFx]FeAs (x = 0.05–0.12) with Tc = 26 K. J. Am. Chem. Soc. 130, 3296–3297 (2008).

    Google Scholar 

  12. Rotter, M., Tegel, M. & Johrendt, D. Superconductivity at 38 K in the iron arsenide (Ba1−xKx)Fe2As2 . Phys. Rev. Lett. 101, 107006 (2008).

    ADS  Google Scholar 

  13. Chu, C. W. et al. The synthesis and characterization of LiFeAs and NaFeAs. Physica C 469, 326–331 (2009).

    ADS  Google Scholar 

  14. Hsu, F-C. et al. Superconductivity in the PbO-type structure α-FeS. Proc. Natl Acad. Sci. USA 105, 14262 (2008).

    ADS  Google Scholar 

  15. Mazin, I. I. Superconductivity gets an iron boost. Nature 464, 183–186 (2010).

    ADS  Google Scholar 

  16. Hirschfeld, P. J., Korshunov, M. M. & Mazin, I. I. Gap symmetry and structure of Fe-based superconductors. Rep. Prog. Phys. 74, 124508 (2011).

    ADS  Google Scholar 

  17. Dong, J. et al. Competing orders and spin-density-wave instability in LaO1−xFxFeAs. Euro. Phys. Lett. 83, 27006 (2008).

    ADS  Google Scholar 

  18. Fawcett, E. Spin-density-wave antiferromagnetism in chromium. Rev. Mod. Phys. 60, 209–283 (1988).

    ADS  Google Scholar 

  19. De la Cruz, C. et al. Magnetic order close to superconductivity in the iron-based layered LaO1−xFxFeAs systems. Nature 453, 899–902 (2008).

    ADS  Google Scholar 

  20. Huang, Q. et al. Neutron-diffraction measurements of magnetic order and a structural transition in the parent BaFe2As2 compound of FeAs-based high-temperature superconductors. Phys. Rev. Lett. 101, 257003 (2008).

    ADS  Google Scholar 

  21. Li, S. et al. Structural and magnetic phase transitions in Na1−δFeAs. Phys. Rev. B 80, 020504 (2009).

    ADS  Google Scholar 

  22. Mazin, I. I., Johannes, M. D., Boeri, L., Koepernik, K. & Singh, D. J. Problems with reconciling density functional theory calculations with experiment in ferropnictides. Phys. Rev. B 78, 085104 (2008).

    ADS  Google Scholar 

  23. Kuroki, K. et al. Unconventional pairing originating from the disconnected Fermi surfaces of superconducting LaFeAsO1−xFx . Phys. Rev. Lett. 101, 087004 (2008).

    ADS  Google Scholar 

  24. Chubukov, A. V. Pairing mechanism in Fe-based superconductors. Annu. Rev. Condens. Matter Phys. 3, 57–92 (2012).

    Google Scholar 

  25. Wang, F. & Lee, D-H. The electron-pairing mechanism of iron-based superconductors. Science 332, 200–204 (2011).

    ADS  Google Scholar 

  26. Eschrig, M. The effect of collective spin-1 excitations on electronic spectra in high-Tc superconductors. Adv. Phys. 55, 47–183 (2006).

    ADS  Google Scholar 

  27. Maier, T. A. & Scalapino, D. J. Theory of neutron scattering as a probe of the superconducting gap in the iron pnictides. Phys. Rev. B 78, 020514 (2008).

    ADS  Google Scholar 

  28. Korshunov, M. M. & Eremin, I. Theory of magnetic excitations in iron-based layered superconductors. Phys. Rev. B 78, 140509 (2008).

    ADS  Google Scholar 

  29. Christianson, A. D. et al. Resonant spin excitation in the high temperature superconductor Ba0.6K0.4Fe2As2 . Nature 456, 930–932 (2008).

    ADS  Google Scholar 

  30. Zhang, C. L. et al. Neutron scattering studies of spin excitations in hole-doped Ba0.67K0.33Fe2As2 superconductor. Sci. Rep. 1, 115 (2011).

    Google Scholar 

  31. Castellan, J-P. et al. Effect of Fermi surface nesting on resonant spin excitations in Ba1−xKxFe2As2 . Phys. Rev. Lett. 107, 177003 (2011).

    ADS  Google Scholar 

  32. Lumsden, M. D. et al. Two-dimensional resonant magnetic excitation in BaFe1.84Co0.16As2 . Phys. Rev. Lett. 102, 107005 (2009).

    ADS  Google Scholar 

  33. Chi, S. et al. Inelastic neutron-scattering measurements of a three-dimensional spin resonance in the FeAs-based BaFe1.9Ni0.1As2 superconductor. Phys. Rev. Lett. 102, 107006 (2009).

    ADS  Google Scholar 

  34. Inosov, D. S. et al. Normal-state spin dynamics and temperature-dependent spin resonance energy in an optimally doped iron arsenide superconductor. Nature Phys. 6, 178 (2010).

    ADS  Google Scholar 

  35. Park, J. T. et al. Symmetry of spin excitation spectra in tetragonal paramagnetic and superconducting phases of 122-ferropnictides. Phys. Rev. B 82, 134503 (2010).

    ADS  Google Scholar 

  36. Lester, C. et al. Dispersive spin fluctuations in the nearly optimally doped superconductor Ba(Fe1−xCox)2As2 (x = 0.065). Phys. Rev. B 81, 064505 (2010).

    ADS  Google Scholar 

  37. Li, H. F. et al. Anisotropic and quasipropagating spin excitations in superconducting Ba(Fe0.926Co0.074)2As2 . Phys. Rev. B 82, 140503 (2010).

    ADS  Google Scholar 

  38. Luo, H. Q. et al. Electron doping evolution of the anisotropic spin excitations in BaFe2−xNixAs2 . Phys. Rev. B 86, 024508 (2012).

    ADS  Google Scholar 

  39. Mook, H. A. et al. Unusual relationship between magnetism and superconductivity in FeTe0.5Se0.5 . Phys. Rev. Lett. 104, 187002 (2010).

    ADS  Google Scholar 

  40. Qiu, Y. et al. Spin gap and resonance at the nesting wave vector in superconducting FeSe0.4Te0.6 . Phys. Rev. Lett. 103, 067008 (2009).

    ADS  Google Scholar 

  41. Lumsden, M. D. et al. Evolution of spin excitations into the superconducting state in FeTe1−xSex . Nature Phys. 6, 182–186 (2010).

    ADS  Google Scholar 

  42. Richard, P., Sato, T., Nakayama, K., Takahashi, T. & Ding, H. Fe-based superconductors: An angle-resolved photoemission spectroscopy perspective. Rep. Prog. Phys. 74, 124512 (2011).

    ADS  Google Scholar 

  43. Si, Q. & Abrahams, E. Strong correlations and magnetic frustration in the high Tc iron pnictides. Phys. Rev. Lett. 101, 076401 (2008).

    ADS  Google Scholar 

  44. Si, Q., Abrahams, E., Dai, J. H. & Zhu, J-X. Correlation effects in the iron pnictides. New J. Phys. 11, 045001 (2009).

    ADS  Google Scholar 

  45. Fang, C., Yao, H., Tsai, W. F., Hu, J. P. & Kivelson, S. A. Theory of electron nematic order in LaOFeAs. Phys. Rev. B 77, 224509 (2008).

    ADS  Google Scholar 

  46. Xu, C. K., Müller, M. & Sachdev, S. Ising and spin orders in the iron-based superconductors. Phys. Rev. B 78, 020501 (2008).

    ADS  Google Scholar 

  47. Seo, K., Bernevig, B. A. & Hu, J. P. Pairing symmetry in a two-orbital exchange coupling model of oxypnictides. Phys. Rev. Lett. 101, 206404 (2008).

    ADS  Google Scholar 

  48. Fang, C. et al. Robustness of s-wave pairing in electron overdoped A1−yFe2−xSe2 . Phy. Rev. X 1, 011009 (2011).

    Google Scholar 

  49. Nicholson, A. et al. Competing pairing symmetries in a generalized two-orbital model for the pnictide superconductors. Phys. Rev. Lett. 106, 217002 (2011).

    ADS  Google Scholar 

  50. Guo, J. G. et al. Superconductivity in the iron selenide KxFe2Se2 (0≤x≤1.0). Phys. Rev. B 82, 180520 (2010).

    ADS  Google Scholar 

  51. Fang, M. H. et al. Fe-based high temperature superconductivity with Tc = 31 K bordering an insulating antiferromagnet in (Tl,K)FexSe2 Crystals. Europhys. Lett. 94, 27009 (2011).

    ADS  Google Scholar 

  52. Wang, X-P. et al. Strong nodeless pairing on separate electron Fermi surface sheets in (Tl,K)Fe1.78Se2 probed by ARPES. Europhys. Lett. 93, 57001 (2011).

    ADS  Google Scholar 

  53. Zhang, Y. et al. Heavily electron-doped electronic structure and isotropic superconducting gap in AxFe2Se2 (A = K,Cs). Nature Mater. 10, 273–277 (2011).

    ADS  Google Scholar 

  54. Mou, D. et al. Distinct Fermi surface topology and nodeless superconducting gap in a (Tl0.58Rb0.42)Fe1.72Se2 superconductor. Phys. Rev. Lett. 106, 107001 (2011).

    ADS  Google Scholar 

  55. Bao, W. et al. A novel large moment antiferromagnetic order in K0.8Fe1.6Se2 superconductor. Chinese Phys. Lett. 28, 086104 (2011).

    ADS  Google Scholar 

  56. Ye, F. et al. Common crystalline and magnetic structure of superconducting A2Fe4Se5 (A = K,Rb,Cs,Tl) single crystals measured using neutron diffraction. Phys. Rev. Lett. 107, 137003 (2011).

    ADS  Google Scholar 

  57. Qazilbash, M. M. et al. Electronic correlations in the iron pnictides. Nature Phys. 5, 647–650 (2009).

    ADS  Google Scholar 

  58. Haule, K., Shim, J. H. & Kotliar, G. Correlated electronic structure of LaO1−xFxFeAs. Phys. Rev. Lett. 100, 226402 (2008).

    ADS  Google Scholar 

  59. Coldea, R. et al. Spin waves and electronic interactions in La2CuO4 . Phys. Rev. Lett. 86, 5377–5380 (2001).

    ADS  Google Scholar 

  60. Headings, N. S., Hayden, S. M., Coldea, R. & Perring, T. G. Anomalous high-energy spin excitations in the high-Tc superconductor-parent antiferromagnet La2CuO4 . Phys. Rev. Lett. 105, 247001 (2010).

    ADS  Google Scholar 

  61. Fang, M. H. et al. Superconductivity close to magnetic instability in Fe(Se1−xTex)0.82 . Phys. Rev. B 78, 224503 (2008).

    ADS  Google Scholar 

  62. Subedi, A., Zhang, L. J., Dingh, D. J. & Du, M. H. Density functional study of FeS, FeSe, and FeTe: Electronic structure, magnetism, phonons, and superconductivity. Phys. Rev. B 78, 134514 (2008).

    ADS  Google Scholar 

  63. Bao, W. et al. Tunable (δ π,δ π)-type antiferromagnetic order in α-Fe(Te,Se) superconductors. Phys. Rev. Lett. 102, 247001 (2009).

    ADS  Google Scholar 

  64. Li, S. L. et al. First-order magnetic and structural phase transitions in Fe1+ySexTe1−x . Phys. Rev. B 79, 054503 (2009).

    ADS  Google Scholar 

  65. Diallo, S. O. et al. Itinerant magnetic excitations in antiferromagnetic CaFe2As2 . Phys. Rev. Lett. 102, 187206 (2009).

    ADS  Google Scholar 

  66. Zhao, J. et al. Spin waves and magnetic exchange interactions in CaFe2As2 . Nature Phys. 5, 555–560 (2009).

    ADS  Google Scholar 

  67. Ewings, R. A. et al. Itinerant spin excitations in SrFe2As2 measured by inelastic neutron scattering. Phys. Rev. B 83, 214519 (2011).

    ADS  Google Scholar 

  68. Harriger, L. W. et al. Nematic spin fluid in the tetragonal phase of BaFe2As2 . Phys. Rev. B 84, 054544 (2011).

    ADS  Google Scholar 

  69. Rodriguez, E. E. et al. Magnetic-crystallographic phase diagram of the superconducting parent compound Fe1+xTe. Phys. Rev. B 84, 064403 (2011).

    ADS  Google Scholar 

  70. Lipscombe, O. J. et al. Spin waves in the (π,0) magnetically ordered iron chalcogenide Fe1.05Te. Phys. Rev. Lett. 106, 057004 (2011).

    ADS  Google Scholar 

  71. Zaliznyak, I. A. et al. Unconventional temperature enhanced magnetism in iron telluride. Phys. Rev. Lett. 107, 216403 (2011).

    ADS  Google Scholar 

  72. Wang, M. Y. et al. Spin waves and magnetic exchange interactions in insulating Rb0.89Fe1.58Se2 . Nature Commun. 2, 580 (2011).

    ADS  Google Scholar 

  73. Ni, N. et al. Effects of Co substitution on thermodynamic and transport properties and anisotropic H c2 in Ba(Fe1−xCox)2As2 single crystals. Phys. Rev. B 78, 214515 (2008).

    ADS  Google Scholar 

  74. Chu, J-H. et al. Determination of the phase diagram of the electron-doped superconductor Ba(Fe1−xCox)2As2 . Phys. Rev. B 79, 014506 (2009).

    ADS  Google Scholar 

  75. Lester, C. et al. Neutron scattering study of the interplay between structure and magnetism in Ba(Fe1−xCox)2As2 . Phys. Rev. B 79, 144523 (2009).

    ADS  Google Scholar 

  76. Pratt, D. K. et al. Coexistence of competing antiferromagnetic and superconducting phases in the underdoped Ba(Fe0.953Co0.047)2As2 compound using X-ray and neutron scattering techniques. Phys. Rev. Lett. 103, 087001 (2009).

    ADS  Google Scholar 

  77. Christianson, A. D. et al. Static and dynamic magnetism in underdoped superconductor BaFe1.92Co0.08As2 . Phys. Rev. Lett. 103, 087002 (2009).

    ADS  Google Scholar 

  78. Wang, M. Y. et al. Electron-doping evolution of the low-energy spin excitations in the iron arsenide superconductor BaFe2−xNixAs2 . Phys. Rev. B 81, 174524 (2010).

    ADS  Google Scholar 

  79. Wang, M. Y. et al. Magnetic field effect on static antiferromagnetic order and spin excitations in the underdoped iron arsenide superconductor BaFe1.92Ni0.08As2 . Phys. Rev. B 83, 094516 (2011).

    ADS  Google Scholar 

  80. Pratt, D. K. et al. Incommensurate spin-density wave order in electron-doped BaFe2As2 superconductors. Phys. Rev. Lett. 106, 257001 (2011).

    ADS  Google Scholar 

  81. Luo, H. Q. et al. Coexistence and competition of the short-range incommensurate antiferromagnetic order with the superconducting state of BaFe2−xNixAs2 . Phys. Rev. Lett. 108, 247002 (2012).

    ADS  Google Scholar 

  82. Nandi, S. et al. Anomalous suppression of the orthorhombic lattice distortion in superconducting Ba(Fe1−xCox)2As2 single crystals. Phys. Rev. Lett. 104, 057006 (2010).

    ADS  Google Scholar 

  83. Chen, H. et al. Coexistence of the spin-density wave and superconductivity in Ba1−xKxFe2As2 . Europhys. Lett. 85, 17006 (2009).

    ADS  Google Scholar 

  84. Park, J. T. et al. Electronic phase separation in the slightly underdoped iron pnictide superconductor Ba1−xKxFe2As2 . Phys. Rev. Lett. 102, 117006 (2009).

    ADS  Google Scholar 

  85. Avci, S. et al. Magnetoelastic coupling in the phase diagram of Ba1−xKxFe2As2 as seen via neutron diffraction. Phys. Rev. B 83, 172503 (2011).

    ADS  Google Scholar 

  86. Wiesenmayer, E. et al. Microscopic coexistence of superconductivity and magnetism in Ba1−xKxFe2As2 . Phys. Rev. Lett. 107, 237001 (2011).

    ADS  Google Scholar 

  87. Graser, S. et al. Spin fluctuations and superconductivity in a three-dimensional tight-binding model for BaFe2As2 . Phys. Rev. B 81, 214503 (2010).

    ADS  Google Scholar 

  88. Zhang, J. H., Sknepnek, R. & Schmalian, J. Spectral analysis for the iron-based superconductors: Anisotropic spin fluctuations and fully gapped s±-wave superconductivity. Phys. Rev. B 82, 134527 (2010).

    ADS  Google Scholar 

  89. Liu, M. S. et al. Nature of magnetic excitations in superconducting BaFe1.9Ni0.1As2 . Nature Phys. 8, 376–381 (2012).

    ADS  Google Scholar 

  90. Lee, C. H. et al. Incommensurate spin fluctuations in hole-overdoped superconductor KFe2As2 . Phys. Rev. Lett. 106, 067003 (2011).

    ADS  Google Scholar 

  91. Park, H., Haule, K. & Kotliar, G. Magnetic excitation spectra in BaFe2As2: A two-particle approach within a combination of the density functional theory and the dynamical mean-field theory method. Phys. Rev. Lett. 107, 137007 (2011).

    ADS  Google Scholar 

  92. Terashima, T. et al. Fermi surface and mass enhancement in KFe2As2 from de Haas-van Alphen effect measurements. J. Phys. Soc. Jpn 79, 053702 (2010).

    ADS  Google Scholar 

  93. Rourke, P. M. C. et al. A detailed de Haas–van Alphen effect study of the overdoped cuprate Tl2Ba2CuO6+δ . New J. Phys. 12, 105009 (2010).

    ADS  Google Scholar 

  94. Nakamura, K., Arita, R. & Imada, M. Ab initio derivation of low-energy model for iron-based superconductors LaFeAsO and LaFePO. J. Phys. Soc. Jpn 77, 093711 (2008).

    ADS  Google Scholar 

  95. Inosov, D. S. et al. Crossover from weak to strong pairing in unconventional superconductors. Phys. Rev. B 83, 214520 (2011).

    ADS  Google Scholar 

  96. Yin, Z. P., Haule, K. & Kotliar, G. Kinetic frustration and the nature of the magnetic and paramagnetic states in iron pnictides and iron chalcogenides. Nature Mater. 10, 932–935 (2011).

    ADS  Google Scholar 

  97. He, C. et al. Electronic-structure-driven magnetic and structure transitions in superconducting NaFeAs single crystals measured by angle-resolved photoemission spectroscopy. Phys. Rev. Lett. 105, 117002 (2010).

    ADS  Google Scholar 

  98. Luo, Q. et al. Neutron and ARPES constraints on the couplings of the multiorbital Hubbard model for the iron pnictides. Phys. Rev. B 82, 104508 (2010).

    ADS  Google Scholar 

  99. Daghofer, M., Nicholson, A., Moreo, A. & Dagotto, E. Three-orbital model for the iron-based superconductors. Phys. Rev. B 81, 014511 (2010).

    ADS  Google Scholar 

  100. Kubo, K. & Thalmeier, P. Correlation effects on antiferromagnetism in Fe pnictides. J. Phys. Soc. Jpn 80, SA121 (2011).

    ADS  Google Scholar 

  101. Miyake, T., Nakamura, K., Arita, R. & Imada, M. Comparison of ab initio low-energy models for LaFePO, BaFe2As2, LiFeAs, FeSe, and FeTe: Electron correlation and covalency. J. Phys. Soc. Jpn 79, 044705 (2010).

    ADS  Google Scholar 

  102. Johannes, M. D. & Mazin, I. I. Microscopic origin of magnetism and magnetic interactions in ferropnictides. Phys. Rev. B 79, 220510 (2009).

    ADS  Google Scholar 

  103. Haule, K. & Kotliar, G. Coherence–incoherence crossover in the normal state of iron oxypnictides and importance of Hund’s rule coupling. New J. Phys. 11, 025021 (2009).

    ADS  Google Scholar 

  104. Lv, W. L., Krüger, F. & Phillips, P. Orbital ordering and unfrustrated (π,0) magnetism from degenerate double exchange in the iron pnictides. Phys. Rev. B 82, 045125 (2010).

    ADS  Google Scholar 

  105. Yin, W-G., Lee, C. C. & Ku, W. Unified picture for magnetic correlations in iron-based superconductors. Phys. Rev. Lett. 105, 107004 (2010).

    ADS  Google Scholar 

  106. Shimojima, T. et al. Orbital-dependent modifications of electronic structure across the magnetostructural transition in BaFe2As2 . Phys. Rev. Lett. 104, 057002 (2010).

    ADS  Google Scholar 

  107. Daghofer, M. et al. Orbital-weight redistribution triggered by spin order in the pnictides. Phys. Rev. B 81, 180514 (2010).

    ADS  Google Scholar 

  108. Fisher, I. R., Degiorgi, L. & Shen, Z. X. In-plane electronic anisotropy of underdoped ‘122’ Fe-arsenide superconductors revealed by measurements of detwinned single crystals. Rep. Prog. Phys. 74, 124506 (2011).

    ADS  Google Scholar 

  109. Tanatar, M. A. et al. Uniaxial-strain mechanical detwinning of CaFe2As2 and BaFe2As2 crystals: Optical and transport study. Phys. Rev. B 81, 814508 (2010).

    Google Scholar 

  110. Zhang, X. T. & Dagotto, E. Anisotropy of the optical conductivity of a pnictide superconductor from the undoped three-orbital Hubbard model. Phys. Rev. B 84, 132505 (2011).

    ADS  Google Scholar 

  111. Fradkin, E., Kivelson, S. A., Lawler, M. J., Eisenstein, J. P. & Mackenzie, A. P. Nematic Fermi fluids in condensed matter physics. Annu. Rev. Condens. Matter Phys. 1, 153–178 (2010).

    ADS  Google Scholar 

  112. Yi, M. et al. Symmetry breaking orbital anisotropy on detwinned Ba(Fe1−xCox)2As2 above the spin density wave transition. Proc. Natl Acad. Sci. USA 108, 6878 (2011).

    ADS  Google Scholar 

  113. Nakajima, M. et al. Unprecedented anisotropic metallic state in undoped iron arsenide BaFe2As2 revealed by optical spectroscopy. Proc. Natl Acad. Sci. USA 108, 12238 (2011).

    ADS  Google Scholar 

  114. Dhital, C. et al. Effect of uniaxial strain on the structural and magnetic phase transitions in BaFe2As2 . Phys. Rev. Lett. 108, 087001 (2012).

    ADS  Google Scholar 

  115. Kasahara, S. et al. Electronic nematicity above the structural and superconducting transition in BaFe2(As1−xPx)2 . Nature 486, 382–385 (2012).

    ADS  Google Scholar 

  116. Fernandes, R. M., Chubukov, A. V., Knolle, J., Eremin, I. & Schmalian, J. Preemptive nematic order, pseudogap, and orbital order in the iron pnictides. Phys. Rev. B 85, 024534 (2012).

    ADS  Google Scholar 

  117. Gretarsson, H. et al. Revealing the dual nature of magnetism in iron pnictides and iron chalcogenides using x-ray emission spectroscopy. Phys. Rev. B 84, 100509 (2011).

    ADS  Google Scholar 

  118. Bondino, F. et al. Evidence for strong itinerant spin fluctuations in the normal state of CeFeAsO0.89F0.11 iron-oxypnictide superconductors. Phys. Rev. Lett. 101, 267001 (2008).

    ADS  Google Scholar 

  119. Hansmann, P. et al. Dichotomy between large local and small ordered magnetic moments in iron-based superconductors. Phys. Rev. Lett. 104, 197002 (2010).

    ADS  Google Scholar 

  120. Shimojima, T. et al. Orbital-independent superconducting gaps in iron pnictides. Science 332, 564–567 (2011).

    ADS  Google Scholar 

  121. Moreo, A. et al. Properties of a two-orbital model for oxypnictide superconductors: Magnetic order, B2g spin-singlet pairing channel, and its nodal structure. Phys. Rev. B 79, 134502 (2009).

    ADS  Google Scholar 

  122. Nicholson, A. et al. Role of degeneracy, hybridization, and nesting in the properties of multi-orbital systems. Phys. Rev. B 84, 094519 (2011).

    ADS  Google Scholar 

  123. Arnold, B. J. et al. Nesting of electron and hole Fermi surfaces in nonsuperconducting BaFe2P2 . Phys. Rev. B 83, 220504 (2011).

    ADS  Google Scholar 

  124. Borisenko, S. V. et al. Superconductivity without nesting in LiFeAs. Phys. Rev. Lett. 105, 067002 (2010).

    ADS  Google Scholar 

  125. Qian, T. et al. Absence of holelike Fermi surface in superconducting K0.8Fe1.7Se2 revealed by ARPES. Phys. Rev. Lett. 106, 187001 (2011).

    ADS  Google Scholar 

  126. Chuang, T-M. et al. Nematic electronic structure in the parent state of the iron-based superconductor Ca(Fe1−xCox)2As2 . Science 327, 181–184 (2010).

    ADS  Google Scholar 

  127. Arita, R. & Ikeda, H. Is Fermi-surface nesting the origin of superconductivity in iron pnictides?: A fluctuation-exchange-approximation study. J. Phys. Soc. Jpn 78, 113707 (2009).

    ADS  Google Scholar 

  128. Dagotto, E., Hotta, T. & Moreo, A. Colossal magnetoresistant materials: The key role of phase separation. Phys. Rep. 344, 1–153 (2001).

    ADS  Google Scholar 

  129. Daghofer, M., Nicholson, A. & Moreo, A. Spectral density in a nematic state of iron pnictides. Phys. Rev. B 85, 184515 (2012).

    ADS  Google Scholar 

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Acknowledgements

We thank L. W. Harriger for preparing the figures shown in this manuscript. We are also grateful to T. A. Maier for calculating the FSs of BaFe2As2 shown in Fig. 2d. P.D. is supported by the US NSF DMR-1063866 (neutron scattering studies on electron-doped iron pnictides), OISE-0968226 (international collaboration) and by US DOE, BES, under Grant No. DE-FG02-05ER46202 (single crystal growth at UTK and neutron scattering studies of hole-doped iron pnictides and other iron-based superconductors). Work at Institute of Physics is supported by the Ministry of Science and Technology of China 973 program (2012CB821400). E.D. is supported by the US DOE, BES, Materials Sciences and Engineering Division and by the US NSF DMR-11-04386.

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P.D. and E.D. wrote the experimental and theoretical portions of the article, respectively. J.P.H. revised the article. All authors discussed the outline of the article.

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Correspondence to Pengcheng Dai or Elbio Dagotto.

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Dai, P., Hu, J. & Dagotto, E. Magnetism and its microscopic origin in iron-based high-temperature superconductors. Nature Phys 8, 709–718 (2012). https://doi.org/10.1038/nphys2438

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