Abstract
Although the existence of nematic order in iron-based superconductors is now a well-established experimental fact, its origin remains controversial. Nematic order breaks the discrete lattice rotational symmetry by making the x and y directions in the iron plane non-equivalent. This can happen because of a regular structural transition or as the result of an electronically driven instability — in particular, orbital order or spin-driven Ising-nematic order. The latter is a magnetic state that breaks rotational symmetry but preserves time-reversal symmetry. Symmetry dictates that the development of one of these orders immediately induces the other two, making the origin of nematicity a physics realization of the ‘chicken and egg problem’. In this Review, we argue that the evidence strongly points to an electronic mechanism of nematicity, placing nematic order in the class of correlation-driven electronic instabilities, like superconductivity and density-wave transitions. We discuss different microscopic models for nematicity and link them to the properties of the magnetic and superconducting states, providing a unified perspective on the phase diagram of the iron pnictides.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Paglione, J. & Greene, R. L. High-temperature superconductivity in iron-based materials. Nature Phys. 6, 645–658 (2010).
Hirschfeld, P. J., Korshunov, M. M. & Mazin, I. I. Gap symmetry and structure of Fe-based superconductors. Rep. Prog. Phys. 74, 124508 (2011).
Chubukov, A. V. Pairing mechanism in Fe-based superconductors. Annu. Rev. Condens. Matter Phys. 3, 57–92 (2012).
Avci, S. et al. Phase diagram of (Ba1−xKx)Fe2As2 . Phys. Rev. B 85, 184507 (2012).
Kim, M. G. et al. Character of the structural and magnetic phase transitions in the parent and electron-doped BaFe2As2 compounds. Phys. Rev. B 83, 134522 (2011).
Rotundu, C. R. & Birgeneau, R. J. First- and second-order magnetic and structural transitions in Ba(Fe1−xCox)2As2 . Phys. Rev. B 84, 092501 (2011).
Kasahara, S. et al. Electronic nematicity above the structural and superconducting transition in BaFe2(As1−xPx)2 . Nature 486, 382–385 (2012).
Zhou, R. et al. Quantum criticality in electron-doped BaFe2−xNixAs2 . Nature Comm. 4, 2265 (2013).
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).
Fang, C., Yao, H., Tsai, W-F., Hu, J. & Kivelson, S. A. Theory of electron nematic order in LaFeAsO. Phys. Rev. B 77, 224509 (2008).
Xu, C., Muller, M. & Sachdev, S. Ising and spin orders in the iron-based superconductors. Phys. Rev. B 78, 020501(R) (2008).
Chandra, P., Coleman, P. & Larkin, A. I. Ising transition in frustrated Heisenberg models. Phys. Rev. Lett. 64, 88–91 (1990).
Chu, J-H. et al. In-plane resistivity anisotropy in an underdoped iron arsenide superconductor. Science 329, 824–826 (2010).
Tanatar, M. A. et al. Uniaxial-strain mechanical detwinning of CaFe2As2 and BaFe2As2 crystals: Optical and transport study. Phys. Rev. B 81, 184508 (2010).
Yi, M. et al. Symmetry-breaking orbital anisotropy observed for detwinned Ba(Fe1−xCox)2As2 above the spin density wave transition. Proc. Natl Acad. Sci. USA 108, 6878–6883 (2011).
Chu, J-H et al. In-plane electronic anisotropy in underdoped Ba(Fe1−xCox)2As2 revealed by partial detwinning in a magnetic field. Phys. Rev. B 81, 214502 (2010).
Nakajima, M. et al. Effect of Co doping on the in-plane anisotropy in the optical spectrum of underdoped Ba(Fe1−xCox)2As2 . Phys. Rev. Lett. 109, 217003 (2012).
Jiang, S. et al. Thermopower as a sensitive probe of electronic nematicity in iron pnictides. Phys. Rev. Lett. 110, 067001 (2013).
Dusza, A. et al. Anisotropic charge dynamics in detwinned Ba(Fe1−xCox)2As2 . Europhys. Lett. 93, 37002 (2011).
Nakajima, M. et al. Unprecedented anisotropic metallic state in undoped iron arsenide BaFe2As2 revealed by optical spectroscopy. Proc. Natl Acad. Sci. USA 108, 12238–12242 (2011).
Fernandes, R. M. & Schmalian, J. Manifestations of nematic degrees of freedom in the magnetic, elastic, and superconducting properties of the iron pnictides. Supercond. Sci. Technol. 25, 084005 (2012).
Cvetkovic, V. & Vafek, O. Space group symmetry, spin-orbit coupling and the low energy effective Hamiltonian for iron based superconductors. Phys. Rev. B 88, 134510 (2013).
Fu, M. et al. NMR search for the spin nematic state in LaFeAsO single crystal. Phys. Rev. Lett. 109, 247001 (2012).
Dhital, C. et al. Effect of uniaxial strain on the structural and magnetic phase transitions in BaFe2As2 . Phys. Rev. Lett. 108, 087001 (2012).
Hu, J., Setty, C. & Kivelson, S. Pressure effects on magnetically driven electronic nematic states in iron pnictide superconductors. Phys. Rev. B 85, 100507 (2012).
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).
Rosenthal, E. P. et al. Visualization of electron nematicity and unidirectional antiferroic fluctuations at high temperatures in NaFeAs. Nature Phys.http://dx.doi.org/10.1038/nphys2870 (2014)
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).
Fernandes, R. M. et al. Effects of nematic fluctuations on the elastic properties of iron arsenide superconductors. Phys. Rev. Lett. 105, 157003 (2010).
Yoshizawa, M. et al. Structural quantum criticality and superconductivity in iron-based superconductor Ba(Fe1−xCox)2As2 . J. Phys. Soc. Jpn 81, 024604 (2012).
Böhmer, A. E. et al. Nematic susceptibility of hole- and electron-doped BaFe2As2 iron-based superconductors. Preprint at http://arxiv.org/abs/1305.3515 (2013)
Gallais, Y. et al. Observation of incipient charge nematicity in Ba(Fe1−xCox)2As2 . Phys. Rev. Lett. 111, 267001 (2013).
Chu, J-H. et al. Divergent nematic susceptibility in an iron arsenide superconductor. Science 337, 710–712 (2012).
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).
Ortenzi, L., Cappelluti, E., Benfatto, L. & Pietronero, L. Fermi surface shrinking and interband coupling in iron-based pnictides. Phys. Rev. Lett. 103, 046404 (2009).
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).
Hardy, F. et al. Evidence of strong correlations and coherence-incoherence crossover in the iron pnictide superconductor KFe2As2 . Phys. Rev. Lett. 111, 027002 (2013).
Chubukov, A. V., Efremov, D. V. & Eremin, I. Magnetism, superconductivity, and pairing symmetry in iron-based superconductors. Phys. Rev. B 78, 134512 (2008).
Eremin, I. & Chubukov, A. V. Magnetic degeneracy and hidden metallicity of the spin-density-wave state in ferrophictides. Phys. Rev. B 81, 024511 (2010).
Dai, P., Hu, J. & Dagotto, E. Magnetism and its microscopic origin in iron-based high-temperature superconductors. Nature Phys. 8, 709–718 (2012).
Brydon, P. M. R., Schmiedt, J. & Timm, C. Microscopically derived Ginzburg-Landau theory for magnetic order in the iron pnictides. Phys. Rev. B 84, 214510 (2011).
Kamiya, Y., Kawashima, N. & Batista, C. D. Dimensional crossover in the quasi-two-dimensional Ising-O(3) model. Phys. Rev. B 84, 214429 (2011).
Qi, Y. & Xu, C. Global phase diagram for magnetism and lattice distortion of iron-pnictide materials. Phys. Rev. B 80, 094402 (2009).
Cano, A., Civelli, M., Eremin, I. & Paul, I. Interplay of magnetic and structural transitions in Fe-based pnictide superconductors. Phys. Rev. B 82, 020408(R) (2010).
Onari, S. & Kontani, H. Self-consistent vertex correction analysis for iron-based superconductors: Mechanism of Coulomb interaction-driven orbital fluctuations. Phys. Rev. Lett. 109, 137001 (2012).
Lv, W. & Phillips, P. Orbitally and magnetically induced anisotropy in iron-based superconductors. Phys. Rev. B 84, 174512 (2011).
Liang, S., Moreo, A. & Dagotto, E. Nematic state of pnictides stabilized by interplay between spin, orbital, and lattice degrees of freedom. Phys. Rev. Lett. 111, 047004 (2013).
Lee, C. C., Yin, W. G. & Ku, W. Ferro-orbital order and strong magnetic anisotropy in the parent compounds of iron-pnictide superconductors. Phys. Rev. Lett. 103, 267001 (2009).
Krüger, F. S., Kumar, J., Zaanen, J. & van den Brink, Spin-orbital frustrations and anomalous metallic state in iron-pnictide superconductors. Phys. Rev. B 79, 054504 (2009).
Applegate, R., Singh, R. R. P., Chen, C-C. & Devereaux, T. P. Phase transitions in spin-orbital models with spin-space anisotropies for iron pnictides: Monte Carlo simulations. Phys. Rev. B 85, 054411 (2012).
Yamase, H. & Zeyher, R. Superconductivity from orbital nematic fluctuations. Phys. Rev. B 88, 180502(R) (2013).
Stanev, V. & Littlewood, P. B. Nematicity driven by hybridization in iron-based superconductors. Phys. Rev. B 87, 161122(R) (2013).
Kang, J. & Tesanovic, Z. Theory of the valley-density wave and hidden order in iron pnictides. Phys. Rev. B 83, 020505 (2011).
Henley, C. L. Ordering due to disorder in a frustrated vector antiferromagnet. Phys. Rev. Lett. 62, 2056–2059 (1989).
Lorenzana, J., Seibold, G., Ortix, C. & Grilli, M. Competing orders in FeAs layers. Phys. Rev. Lett. 101, 186402 (2008).
Avci, S. et al. The origin of nematic order in the iron-based superconductors. Preprint at http://arxiv.org/abs/1303.2647 (2013)
Kim, M. G. et al. Antiferromagnetic ordering in the absence of a structural distortion in Ba(Fe1−xMnx)2As2 . Phys. Rev. B 82, 220503(R) (2010).
Valenzuela, B., Bascones, E. & Calderon, M. J. Conductivity anisotropy in the antiferromagnetic state of iron pnictides. Phys. Rev. Lett. 105, 207202 (2010).
Chen, C-C., Maciejko, J., Sorini, A. P., Moritz, B., Singh, R. R. P. & Devereaux, T. P. Orbital order and spontaneous orthorhombicity in iron pnictides. Phys. Rev. B 82, 100504 (2010).
Fernandes, R. M., Abrahams, E. & Schmalian, J. Anisotropic in-plane resistivity in the nematic phase of the iron pnictides. Phys. Rev. Lett. 107, 217002 (2011).
Blomberg, E. C. et al. Sign-reversal of the in-plane resistivity anisotropy in hole-doped iron pnictides. Nature Commun. 4, 1914 (2013).
Goswami, P., Yu, R., Si, Q. & Abrahams, E. Spin dynamics of a J1 − J2 antiferromagnet and its implications for iron pnictides. Phys. Rev. B 84, 155108 (2011).
Ma, L. et al. 23Na and 75As NMR study of antiferromagnetism and spin fluctuations in NaFeAs single crystals. Phys. Rev. B 83, 132501 (2011).
Shimojima, T. et al. Pseudogap formation above the superconducting dome in iron-pnictides. Phys. Rev. B 89, 045101 (2013).
Lee, W-C. & Phillips, P. W. Non-Fermi liquid due to orbital fluctuations in iron pnictide superconductors. Phys. Rev. B 86, 245113 (2012).
Arham, H. Z. et al. Detection of orbital fluctuations above the structural transition temperature in the iron pnictides and chalcogenides. Phys. Rev. B 85, 214515 (2012).
Fernandes, R. M., Böhmer, A. E., Meingast, C. & Schmalian, J. Scaling between magnetic and lattice fluctuations in iron-pnictide superconductors. Phys. Rev. Lett. 111, 137001 (2013).
Moon, E. G. & Sachdev, S. Competition between superconductivity and nematic order: Anisotropy of superconducting coherence length. Phys. Rev. B 85, 184511 (2012).
Reid, J-Ph. et al. Universal heat conduction in the iron-arsenide superconductor KFe2As2: Evidence of a d-wave state. Phys. Rev. Lett. 109, 087001 (2012).
Fernandes, R. M. & Millis, A. J. Nematicity as a probe of superconducting pairing in iron-based superconductors. Phys. Rev. Lett. 111, 127001 (2013).
Livanas, G., Aperis, A., Kotetes, P. & Varelogiannis, G. Nematicity from mixed s+− + states in iron-based superconductors. Preprint at http://arxiv.org/abs/1208.2881 (2012)
Yang, F., Wang, F. & Lee, D-H. Fermiology, orbital order, orbital fluctuation and cooper pairing in iron-based superconductors. Phys. Rev. B 88, 100504 (2013).
Fernandes, R. M., Maiti, S., Wölfle, P. & Chubukov, A. V. How many quantum phase transitions exist inside the superconducting dome of the iron pnictides?. Phys. Rev. Lett. 111, 057001 (2013).
Acknowledgements
We acknowledge useful discussions with E. Abrahams, J. Analytis, E. Bascones, A. Böhmer, J. van den Brink, P. Brydon, S. Bud’ko, P. Canfield, P. Chandra, P. Dai, M. Daghofer, L. Degiorgi, I. Eremin, I. Fisher, Y. Gallais, A. Goldman, A. Kaminski, J. Kang, V. Keppens, D. Khalyavin, M. Khodas, S. Kivelson, J. Knolle, H. Kontani, A. Kreyssig, F. Krüger, W. Ku, W.C. Lee, J. Lorenzana, W. Lv, S. Maiti, D. Mandrus, R. McQueeney, Y. Matsuda, I. Mazin, C. Meingast, A. Millis, P. Orth, R. Osborn, A. Pasupathy, I. Paul, P. Phillips, R. Prozorov, S. Sachdev, Q. Si, T. Shibauchi, L. Taillefer, M. Takigawa, M. Tanatar, M. Vavilov, P. Wölfle and M. Yoshizawa. The authors benefited much from discussions with our colleague Z. Tesanovic, who unexpectedly passed away last year. A.V.C. is supported by the Office of Basic Energy Sciences US Department of Energy under the grant #DE-FG02-ER46900. J.S. is supported by the Deutsche Forschungsgemeinschaft through DFG-SPP 1458 ‘Hochtemperatursupraleitung in Eisenpniktiden’.
Author information
Authors and Affiliations
Contributions
All authors were responsible for writing and revising the paper.
Corresponding authors
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Rights and permissions
About this article
Cite this article
Fernandes, R., Chubukov, A. & Schmalian, J. What drives nematic order in iron-based superconductors?. Nature Phys 10, 97–104 (2014). https://doi.org/10.1038/nphys2877
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nphys2877
This article is cited by
-
High-temperature superconductivity with zero resistance and strange-metal behaviour in La3Ni2O7−δ
Nature Physics (2024)
-
Unconventional superconductivity near a nematic instability in a multi-orbital system
npj Quantum Materials (2024)
-
Order from disorder phenomena in BaCoS2
Communications Physics (2024)
-
Optimized superconductivity in the vicinity of a nematic quantum critical point in the kagome superconductor Cs(V1-xTix)3Sb5
Nature Communications (2023)
-
Anomalous excitonic phase diagram in band-gap-tuned Ta2Ni(Se,S)5
Nature Communications (2023)