Puddle formation and persistent gaps across the non-mean-field breakdown of superconductivity in overdoped (Pb,Bi)2Sr2CuO6+δ
Source abstract
Abstract
Abstract The cuprate high-temperature superconductors exhibit many unexplained electronic phases, but the superconductivity at high doping is often believed to be governed by conventional mean-field Bardeen–Cooper–Schrieffer theory1. However, it was shown that the superfluid density vanishes when the transition temperature goes to zero2,3, in contradiction to expectations from Bardeen–Cooper–Schrieffer theory. Our scanning tunnelling spectroscopy measurements in the overdoped regime of the (Pb,Bi)2Sr2CuO6+δ high-temperature superconductor show that this is due to the emergence of nanoscale superconducting puddles in a metallic matrix4,5. Our measurements further reveal that this puddling is driven by gap filling instead of gap closing. The important implication is that it is not a diminishing pairing interaction that causes the breakdown of superconductivity. Unexpectedly, the measured gap-to-filling correlation also reveals that pair breaking by disorder does not play a dominant role and that the mechanism of superconductivity in overdoped cuprate superconductors is qualitatively different from conventional mean-field theory.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Physics of Superconductivity and Magnetism · Advanced Condensed Matter Physics · Magnetic properties of thin films
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (32)
Show source-provided references
1. Keimer, B., Kivelson, S. A., Norman, M. R., Uchida, S. & Zaanen, J. From quantum matter to high-temperature superconductivity in copper oxides. Nature 518, 179–186 (2015).10.1038/nature14165 ↗
2. Bozovic, I., He, X., Wu, J. & Bollinger, A. T. Dependence of the critical temperature in overdoped copper oxides on superfluid density. Nature 536, 309–311 (2016).10.1038/nature19061 ↗
3. Uemura, Y. J. et al. Magnetic-field penetration depth in Tl2Ba2CuO6+δ in the overdoped regime. Nature 364, 605–607 (1993).10.1038/364605a0 ↗
4. Li, Z.-X., Kivelson, S. & Lee, D.-H. The superconductor to metal transition in overdoped cuprates. npj Quantum Mater. 6, 36 (2021).10.1038/s41535-021-00335-4 ↗
5. Lee-Hone, N. R., Özdemir, H. U., Mishra, V., Broun, D. M. & Hirschfeld, P. J. Low energy phenomenology of the overdoped cuprates: viability of the Landau-BCS paradigm. Phys. Rev. Res. 2, 013228 (2020).10.1103/PhysRevResearch.2.013228 ↗
6. Vignolle, B. et al. Quantum oscillations in an overdoped high-Tc superconductor. Nature 455, 952–955 (2008).10.1038/nature07323 ↗
7. Fujita, K. et al. Simultaneous transitions in cuprate momentum-space topology and electronic symmetry breaking. Science 344, 612–616 (2014).10.1126/science.1248783 ↗
8. Chen, S.-D. et al. Incoherent strange metal sharply bounded by a critical doping in Bi2212. Science 366, 1099–1102 (2019).10.1126/science.aaw8850 ↗
9. He, Y. et al. Rapid change of superconductivity and electron-phonon coupling through critical doping in Bi-2212. Science 362, 62–65 (2018).10.1126/science.aar3394 ↗
10. Valla, T., Drozdov, I. K. & Gu, G. D. Disappearance of superconductivity due to vanishing coupling in the overdoped Bi2Sr2CaCu2O8+δ. Nat. Commun. 11, 569 (2020).10.1038/s41467-020-14282-4 ↗
11. Ayres, J. et al. Incoherent transport across the strange metal regime of highly overdoped cuprates. Nature 595, 661–666 (2021).10.1038/s41586-021-03622-z ↗
12. Mahmood, F., He, X., BoŽović, I. & Armitage, N. P. Locating the missing superconducting electrons in the overdoped cuprates La2–xSrxCuO4. Phys. Rev. Lett. 122, 027003 (2019).10.1103/PhysRevLett.122.027003 ↗
13. Bouadim, K., Loh, Y. L., Randeria, M. & Trivedi, N. Single- and two-particle energy gaps across the disorder-driven superconductor–insulator transition. Nat. Phys. 7, 884–889 (2011).10.1038/nphys2037 ↗
14. Spivak, B., Oreto, P. & Kivelson, S. A. Theory of quantum metal to superconductor transitions in highly conducting systems. Phys. Rev. B 77, 214523 (2008).10.1103/PhysRevB.77.214523 ↗
15. Dodaro, J. F. & Kivelson, S. A. Generalization of Anderson’s theorem for disordered superconductors. Phys. Rev. B 98, 174503 (2018).10.1103/PhysRevB.98.174503 ↗
16. Ghosal, A., Randeria, M. & Trivedi, N. Role of spatial amplitude fluctuations in highly disordered s-wave superconductors. Phys. Rev. Lett. 81, 3940–3943 (1998).10.1103/PhysRevLett.81.3940 ↗
17. Putzke, C. et al. Reduced Hall carrier density in the overdoped strange metal regime of cuprate superconductors. Nat. Phys. 17, 826–831 (2021).10.1038/s41567-021-01197-0 ↗
18. Piriou, A., Jenkins, N., Berthod, C., Maggio-Aprile, I. & Fischer, O. First direct observation of the van Hove singularity in the tunnelling spectra of cuprates. Nat. Commun. 2, 221 (2011).10.1038/ncomms1229 ↗
19. Li, X. et al. Quasiparticle interference and charge order in a heavily overdoped non-superconducting cuprate. New J. Phys. 20, 063041 (2018).10.1088/1367-2630/aacb5e ↗
20. Alldredge, J. W. et al. Evolution of the electronic excitation spectrum with strongly diminishing hole density in superconducting Bi2Sr2CaCu2O8+δ. Nat. Phys. 4, 319–326 (2008).10.1038/nphys917 ↗
21. Dynes, R. C., Narayanamurti, V. & Garno, J. P. Direct measurement of quasiparticle-lifetime broadening in a strong-coupled superconductor. Phys. Rev. Lett. 41, 1509–1512 (1978).10.1103/PhysRevLett.41.1509 ↗
22. Li, Y. et al. Strongly-overdoped La2−xSrxCuO4: evidence for Josephson-coupled grains of strongly-correlated superconductor. Phys. Rev. B 106, 224515 (2022).10.1103/PhysRevB.106.224515 ↗
23. He, Y. et al. Superconducting fluctuations in overdoped Bi2Sr2CaCu2O8+δ. Phys. Rev. X 11, 031068 (2021).
24. Franz, M. & Millis, A. Phase fluctuations and spectral properties of underdoped cuprates. Phys. Rev. B 58, 14572–14580 (1998).10.1103/PhysRevB.58.14572 ↗
25. Berg, E. & Altman, E. Evolution of the Fermi surface of d-wave superconductors in the presence of thermal phase fluctuations. Phys. Rev. Lett. 99, 247001 (2007).10.1103/PhysRevLett.99.247001 ↗
26. Kondo, T. et al. Disentangling Cooper-pair formation above the transition temperature from the pseudogap state in the cuprates. Nat. Phys. 7, 21–25 (2011).10.1038/nphys1851 ↗
27. Fang, A. C. et al. Gap-inhomogeneity-induced electronic states in superconducting Bi2Sr2CaCu2O8+δ. Phys. Rev. Lett. 96, 017007 (2006).10.1103/PhysRevLett.96.017007 ↗
28. Pasupathy, A. N. et al. Electronic origin of the inhomogeneous pairing interaction in the high-Tc superconductor Bi2Sr2CaCu2O8+δ. Science 320, 196–201 (2008).10.1126/science.1154700 ↗
29. Parker, C. V. et al. Nanoscale proximity effect in the high-temperature superconductor Bi2Sr2CaCu2O8+δ using a scanning tunneling microscope. Phys. Rev. Lett. 104, 117001 (2010).10.1103/PhysRevLett.104.117001 ↗
30. Bastiaans, K. M. et al. Direct evidence for Cooper pairing without a spectral gap in a disordered superconductor above Tc. Science 374, 608–611 (2021).10.1126/science.abe3987 ↗
31. Božović, I. & Levy, J. Pre-formed Cooper pairs in copper oxides and LaAlO3—SrTiO3 heterostructures. Nat. Phys. 16, 712–717 (2020).10.1038/s41567-020-0915-8 ↗
32. He, Y. et al. Fermi surface and pseudogap evolution in a cuprate superconductor. Science 344, 612–616 (2014).10.1126/science.1248221 ↗