Letter | Published:

Thermodynamic signature of a magnetic-field-driven phase transition within the superconducting state of an underdoped cuprate

Nature Physics volume 12, pages 4751 (2016) | Download Citation

Abstract

More than a quarter century after the discovery of the high-temperature superconductor (HTS) YBa2Cu3O6+δ (YBCO; ref. 1), studies continue to uncover complexity in its phase diagram. In addition to HTS and the pseudogap2,3, there is growing evidence for multiple phases with boundaries which are functions of temperature (T), doping (p) and magnetic field4,5,6,7,8. Here we report the low-temperature electronic specific heat (Celec) of YBa2Cu3O6.43 and YBa2Cu3O6.47 (p = 0.076 and 0.084) up to a magnetic field (H) of 34.5 T, a poorly understood region of the underdoped HTp phase space. We observe two regimes in the low-temperature limit: below a characteristic magnetic field H′ ≈ 12–15 T, Celec/T obeys an expected H1/2 behaviour9,10; however, near H′ there is a sharp inflection followed by a linear-in-H behaviour. H′ rests deep within the superconducting phase and, thus, the linear-in-H behaviour is observed in the zero-resistance regime11. In the limit of zero temperature, Celec/T is proportional to the zero-energy electronic density of states. At one of our dopings, the inflection is sharp only at lowest temperatures, and we thus conclude that this inflection is evidence of a magnetic-field-driven quantum phase transition.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    et al. Superconductivity at 93 K in a new mixed-phase Y–Ba–Cu–O compound system at ambient pressure. Phys. Rev. Lett. 58, 908–910 (1987).

  2. 2.

    , & 89Y NMR evidence for a Fermi-liquid behavior in YBa2Cu3O6+x. Phys. Rev. Lett. 63, 1700–1703 (1989).

  3. 3.

    & Nuclear resonance properties of YBa2Cu3O6+x superconductors. Science 248, 1082–1087 (1990).

  4. 4.

    et al. Spin-glass state of individual magnetic vortices in YBa2Cu3Oy and La2−xSrxCuO4 below the metal-to-insulator crossover. Phys. Rev. B 76, 064522 (2007).

  5. 5.

    , , , & Magnetic states of lightly hole-doped cuprates in the clean limit as seen via zero-field muon spin spectroscopy. Phys. Rev. B 81, 104507 (2010).

  6. 6.

    et al. Neutron scattering study of the magnetic phase diagram of underdoped YBa2Cu3O6+x. New J. Phys. 12, 105006 (2010).

  7. 7.

    et al. Emergence of charge order from the vortex state of a high-temperature superconductor. Nature Commun. 4, 2113 (2013).

  8. 8.

    et al. Long-range incommensurate charge fluctuations in (Y, Nd)Ba2Cu3O6+x. Science 337, 821–825 (2012).

  9. 9.

    Superconductivity with lines of gap nodes: Density of states in the vortex. JETP Lett. 58, 457–461 (1993).

  10. 10.

    & Scaling of the quasiparticle spectrum for d-wave superconductors. Phys. Rev. Lett. 78, 1548–1551 (1997).

  11. 11.

    et al. Vortex lattice melting and Hc2 in underdoped YBa2Cu3Oy. Phys. Rev. B 86, 174501 (2012).

  12. 12.

    & Singularity of the vortex density of states in d-wave superconductors. JETP Lett. 64, 690–694 (1996).

  13. 13.

    et al. Magnetic field dependence of the density of states of YBa2Cu3O6.95 as determined from the specific heat. Phys. Rev. Lett. 73, 2744–2747 (1994).

  14. 14.

    , , & Direct observation and anisotropy of the contribution of gap nodes in the low-temperature specific heat of YBa2Cu3O7. Phys. Rev. B 63, 094508 (2001).

  15. 15.

    , & Evaluation of CuO2 plane hole doping in YBa2Cu3O6+x single crystals. Phys. Rev. B. 73, 180505 (2006).

  16. 16.

    et al. Heat capacity through the magnetic-field-induced resistive transition in an underdoped high-temperature superconductor. Nature Phys. 7, 332–335 (2011).

  17. 17.

    & d-wave superconductivity in doped Mott insulators. J. Phys. Chem. Solids 63, 2259–2268 (2002).

  18. 18.

    & Berry phases and the intrinsic thermal Hall effect in high-temperature cuprate superconductors. Nature Commun. 6, 6518 (2015).

  19. 19.

    et al. Extending universal nodal excitations optimizes superconductivity in Bi2Sr2CaCu2O8+δ. Science 324, 1689–1693 (2009).

  20. 20.

    et al. Phase competition in trisected superconducting dome. Proc. Natl Acad. Sci. USA 109, 18332–18337 (2012).

  21. 21.

    et al. Pseudogap, superconducting energy scale, and Fermi arcs of underdoped cuprate superconductors. Phys. Rev. B 72, 134507 (2005).

  22. 22.

    et al. Doping-dependent nodal Fermi velocity of the high-temperature superconductor Bi2Sr2CaCu2O8+δ revealed using high-resolution angle-resolved photoemission spectroscopy. Phys. Rev. Lett. 104, 207002 (2010).

  23. 23.

    , & Magnetic-field dependence of thermodynamic quantities in the vortex state of type-II superconductors. Phys. Rev. B 71, 144515 (2005).

  24. 24.

    & Quantum oscillations in the mixed state of d-wave superconductors. Phys. Rev. B 78, 020502 (2008).

  25. 25.

    & Response of a dx2-y2 superconductor to a Zeeman magnetic field. Phys. Rev. B 57, 8566–8570 (1998).

  26. 26.

    et al. Metal–insulator quantum critical point beneath the high Tc superconducting dome. Proc. Natl Acad. Sci. USA 107, 6175–6179 (2010).

  27. 27.

    et al. Lifshitz critical point in the cuprate superconductor YBa2Cu3Oy from high-field Hall effect measurements. Phys. Rev. B 83, 054506 (2011).

  28. 28.

    et al. Competing charge, spin, and superconducting orders in underdoped YBa2Cu3Oy. Phys. Rev. B 90, 054514 (2014).

  29. 29.

    et al. Field-induced transition between magnetically disordered and ordered phases in underdoped La2−xSrxCuO4. Phys. Rev. B 71, 220508 (2005).

  30. 30.

    et al. Thermal conductivity across the phase diagram of cuprates: Low-energy quasiparticles and doping dependence of the superconducting gap. Phys. Rev. B 67, 174520 (2003).

Download references

Acknowledgements

The authors thank S. Kivelson, R. Baumbach, A. Kapitulnik, M. Norman, B. Ramshaw, A. Shekhter, J. Sonier and S. Riggs for discussions and commentary on the manuscript, as well as A. Migliori for discussions on the experimental techniques. J.B.K. thanks C. Moir for assistance during experiments. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-1157490, the State of Florida, and the US Department of Energy. Work at the University of British Columbia was supported by the Natural Science and Engineering Research Council of Canada and the Canadian Institute for Advanced Research.

Author information

Affiliations

  1. Department of Physics and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA

    • J. B. Kemper
    • , O. Vafek
    •  & G. S. Boebinger
  2. National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

    • J. B. Betts
    •  & F. F. Balakirev
  3. Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada

    • W. N. Hardy
    • , Ruixing Liang
    •  & D. A. Bonn
  4. Canadian Institute for Advanced Research, 180 Dundas Street West, Suite 1400, Toronto, Ontario M5G 1Z8, Canada

    • W. N. Hardy
    • , Ruixing Liang
    •  & D. A. Bonn

Authors

  1. Search for J. B. Kemper in:

  2. Search for O. Vafek in:

  3. Search for J. B. Betts in:

  4. Search for F. F. Balakirev in:

  5. Search for W. N. Hardy in:

  6. Search for Ruixing Liang in:

  7. Search for D. A. Bonn in:

  8. Search for G. S. Boebinger in:

Contributions

W.N.H., R.L. and D.A.B. prepared the samples and contributed to the experimental plan. J.B.K. refined the experimental set-up, performed the experiments, analysed the data and contributed to the writing of the manuscript. O.V. contributed to the writing of the manuscript and interpretation of results. G.S.B. supervised the project and contributed to the writing of the manuscript. F.F.B. contributed to the experimental software and thermometer calibrations. J.B.B. contributed to the experimental hardware and thermometer calibrations. F.F.B., J.B.B. and D.A.B. provided comments on the results and manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to J. B. Kemper.

Supplementary information

PDF files

  1. 1.

    Supplementary information

    Supplementary information

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nphys3502

Further reading