In a classical Bardeen–Cooper–Schrieffer superconductor, pairing and coherence of electrons are established simultaneously below the critical transition temperature (Tc), giving rise to a gap in the electronic energy spectrum. In the high-Tc copper oxide superconductors, however, a pseudogap1,2,3,4,5,6,7,8 extends above Tc. The relationship between the pseudogap and superconductivity is one of the central issues in this field9,10,11,12,13,14,15,16,17. Spectral gaps arising from pairing precursors are qualitatively similar to those caused by competing electronic states, rendering a standard approach to their analysis inconclusive10,11,12,13,14,15,16. The issue can be settled, however, by studying the correlation between the weights associated with the pseudogap and superconductivity spectral features. Here we report a study of two spectral weights using angle-resolved photoemission spectroscopy. The weight of the superconducting coherent peak increases away from the node following the trend of the superconducting gap, but starts to decrease in the antinodal region. This striking non-monotonicity reveals the presence of a competing state. We demonstrate a direct correlation, for different values of momenta and doping, between the loss in the low-energy spectral weight arising from the opening of the pseudogap and a decrease in the spectral weight associated with superconductivity. We therefore conclude that the pseudogap competes with the superconductivity by depleting the spectral weight available for pairing.
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Emery, V. J. & Kivelson, S. A. Importance of phase fluctuations in superconductors with small superfluid density. Nature 374, 434–437 (1995)
Ding, H. et al. Spectroscopic evidence for a pseudogap in the normal state of underdoped high-T c superconductors. Nature 382, 51–54 (1996)
Loeser, A. G. et al. Excitation gap in the normal state of underdoped Bi2Sr2CaCu2O8+x . Science 273, 325–329 (1996)
Norman, M. R. et al. Destruction of the Fermi surface in underdoped high-T c superconductors. Nature 392, 157–160 (1998)
Timusk, T. & Statt, B. The pseudogap in high-temperature superconductors: an experimental survey. Rep. Prog. Phys. 62, 61–122 (1999)
Damascelli, A., Hussain, Z. & Shen, Z.-X. Angle-resolved photoemission studies of the cuprate superconductors. Rev. Mod. Phys. 75, 473–541 (2003)
Campuzano, J. C., Norman, M. R. & Randeria, M. in The Physics of Superconductors Vol. II (eds Bennemann, K. H. & Ketterson, J. B.) 167–273 (Springer, 2004)
Anderson, P. W. et al. The physics behind high-temperature superconducting cuprates: The “plain vanilla” version of RVB. J. Phys. Condens. Matter 16, R755–R769 (2004)
Le Tacon, M. et al. Two energy scales and two distinct quasiparticle dynamics in the superconducting state of underdoped cuprates. Nature Phys. 2, 537–543 (2006)
Tanaka, K. et al. Distinct Fermi-momentum-dependent energy gaps in deeply underdoped Bi2212. Science 314, 1910–1913 (2006)
Lee, W. S. et al. Abrupt onset of a second energy gap at the superconducting transition of underdoped Bi2212. Nature 450, 81–84 (2007)
Kondo, T., Takeuchi, T., Kaminski, A., Tsuda, S. & Shin, S. Evidence for two energy scales in the superconducting state of optimally doped (Bi,Pb)2(Sr,La)2CuO6+x . Phys. Rev. Lett. 98, 267004 (2007)
Boyer, M. C. et al. Imaging the two gaps of the high-temperature superconductor Bi2Sr2CuO6+x . Nature Phys. 3, 802–806 (2007)
Khasanov, R. et al. Evidence for competition between the superconducting and the pseudogap state in (BiPb)2(SrLa)2CuO6+δ from muon-spin rotation experiments. Phys. Rev. Lett. 101, 227002 (2008)
Kanigel, A. et al. Evidence for pairing above Tc from the dispersion in the pseudogap phase of cuprates. Phys. Rev. Lett. 101, 137002 (2008)
Johnson, P. D. et al. Emergence of preformed Cooper pairs from the doped Mott insulating state in Bi2Sr2CaCu2O8+δ . Nature 456, 77–80 (2008)
Norman, M. R., Pines, D. & Kallin, C. The pseudogap: friend or foe of high Tc? Adv. Phys. 54, 715–733 (2005)
Loeser, A. G. et al. Temperature and doping dependence of the Bi-Sr-Ca-Cu-O electronic structure and fluctuation effects. Phys. Rev. B 56, 14185–14189 (1997)
Wei, J. et al. Superconducting coherence peak in the electronic excitations of a single layer cuprate superconductor Bi2Sr1. 6La0. 4CuO6+δ . Phys. Rev. Lett. 101, 097005 (2008)
Feng, D. L. et al. Signature of superfluid density in the single-particle excitation spectrum of Bi2Sr2CaCu2O8+x . Science 289, 277–281 (2000)
Ding, H. et al. Coherent quasiparticle weight and its connection to high-T c superconductivity from angle-resolved photoemission. Phys. Rev. Lett. 87, 227001 (2001)
Russo, P. L. et al. Muon spin relaxation study of superconducting Bi2Sr2-xLaxCuO6+x . Phys. Rev. B 75, 054511 (2007)
Shi, M. et al. The coherent d-wave superconducting gap in underdoped La2-xSrxCuO4 as studied by angle-resolved photoemission. Phys. Rev. Lett. 101, 047002 (2008)
Varma, C. M. Non-Fermi-liquid states and pairing instability of a general model of copper oxide metals. Phys. Rev. B 55, 14554–14580 (1997)
Schmalian, J., Pines, D. & Stojkovic, B. Weak pseudogap behavior in the underdoped cuprate superconductors. Phys. Rev. Lett. 80, 3839–3842 (1998)
Emery, V. J., Kivelson, S. A. & Tranquada, J. M. Stripe phases in high-temperature superconductors. Proc. Natl Acad. Sci. USA 96, 8814–8817 (1999)
Chakravarty, S., Laughlin, R. B., Morr, D. K. & Nayak, C. Hidden order in the cuprates. Phys. Rev. B 63, 094503 (2001)
Hanaguri, T. et al. A ‘checkerboard’ electronic crystal state in lightly hole-doped Ca2-x Na x CuO2Cl2 . Nature 430, 1001–1005 (2004)
Wise, W. D. et al. Charge-density-wave origin of cuprate checkerboard visualized by scanning tunnelling microscopy. Nature Phys. 4, 696–699 (2008)
Balents, L., Bartosch, L., Burkov, A., Sachdev, S. & Sengupta, K. Putting competing orders in their place near the Mott transition. II. The doped quantum dimer model. Phys. Rev. B 71, 144509 (2005)
We thank A. J. Millis, C. Varma and H. M. Fretwell for discussions. This work was supported by Basic Energy Sciences, US Department of Energy. The Ames Laboratory is operated for the US Department of Energy, Basic Energy Sciences, by Iowa State University under contract no. DE-AC02-07CH11358.
Author Contributions T.K., R.K. and A.K. designed the experiment. T.K. and T.T. grew the high-quality single crystals. T.K. acquired the experimental data and T.K. and A.K. performed the data analysis. T.K., A.K. and J.S. wrote the manuscript. All authors discussed the results and commented on the manuscript.
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Kondo, T., Khasanov, R., Takeuchi, T. et al. Competition between the pseudogap and superconductivity in the high-Tc copper oxides. Nature 457, 296–300 (2009). https://doi.org/10.1038/nature07644
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