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Linear-in-temperature resistivity for optimally superconducting (Nd,Sr)NiO2

Abstract

The occurrence of superconductivity in proximity to various strongly correlated phases of matter has drawn extensive focus on their normal state properties, to develop an understanding of the state from which superconductivity emerges1,2,3,4. The recent finding of superconductivity in layered nickelates raises similar interests5,6,7,8. However, transport measurements of doped infinite-layer nickelate thin films have been hampered by materials limitations of these metastable compounds: in particular, a high density of extended defects9,10,11. Here, by moving to a substrate (LaAlO3)0.3(Sr2TaAlO6)0.7 that better stabilizes the growth and reduction conditions, we can synthesize the doping series of Nd1–xSrxNiO2 essentially free from extended defects. In their absence, the normal state resistivity shows a low-temperature upturn in the underdoped regime, linear behaviour near optimal doping and quadratic temperature dependence for overdoping. This is phenomenologically similar to the copper oxides2,12 despite key distinctions—namely, the absence of an insulating parent compound5,6,9,10, multiband electronic structure13,14 and a Mott–Hubbard orbital alignment rather than the charge-transfer insulator of the copper oxides15,16. We further observe an enhancement of superconductivity, both in terms of transition temperature and range of doping. These results indicate a convergence in the electronic properties of both superconducting families as the scale of disorder in the nickelates is reduced.

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Fig. 1: Enhanced crystallinity of Nd1–xSrxNiO2 thin films on LSAT.
Fig. 2: Phase diagram of highly crystalline Nd1–xSrxNiO2.
Fig. 3: Magnetotransport characteristics of the underdoped regime.
Fig. 4: Magnetotransport characteristics of the overdoped regime.

Data availability

The data that support the findings of this study are available from the corresponding author upon request.

References

  1. 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  CAS  ADS  Google Scholar 

  2. 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).

    Article  CAS  PubMed  ADS  Google Scholar 

  3. Cao, Y. et al. Unconventional superconductivity in magic-angle graphene superlattices. Nature 556, 43–50 (2018).

    Article  CAS  PubMed  ADS  Google Scholar 

  4. Fernandes, R. M. et al. Iron pnictides and chalcogenides: a new paradigm for superconductivity. Nature 601, 35–44 (2022).

    Article  CAS  PubMed  ADS  Google Scholar 

  5. Li, D. et al. Superconductivity in an infinite-layer nickelate. Nature 572, 624–627 (2019).

    Article  CAS  PubMed  ADS  Google Scholar 

  6. Osada, M. et al. Nickelate superconductivity without rare-earth magnetism: (La,Sr)NiO2. Adv. Mater. 2021, 2104083 (2021).

  7. Pan, G. A. et al. Superconductivity in a quintuple-layer square-planar nickelate. Nat. Mater. 21, 160–164 (2022).

  8. Zeng, S. et al. Superconductivity in infinite-layer nickelate La1−xCaxNiO2 thin films. Sci. Adv. 8, eabl9927 (2022).

  9. Li, D. et al. Superconducting dome in Nd1–xSrxNiO2 infinite layer films. Phys. Rev. Lett. 125, 027001 (2020).

  10. Zeng, S. et al. Phase diagram and superconducting dome of infinite-layer Nd1–xSrxNiO2 thin films. Phys. Rev. Lett. 125, 147003 (2020).

  11. Lee, K. et al. Aspects of the synthesis of thin film superconducting infinite-layer nickelates. APL Mater. 8, 041107 (2020).

  12. Takagi, H. et al. Superconductor-to-nonsuperconductor transition in (La1–xSrx)2CuO4 as investigated by transport and magnetic measurements. Phys. Rev. B 40, 2254–2261 (1989).

  13. Lee, K. W. & Pickett, W. E. Infinite-layer LaNiO2: Ni1+ is not Cu2+. Phys. Rev. B 70, 165109 (2004).

  14. Botana, A. S. & Norman, M. R. Similarities and differences between LaNiO2 and CaCuO2 and implications for superconductivity. Phys. Rev. X 10, 011024 (2020).

  15. Hepting, M. et al. Electronic structure of the parent compound of superconducting infinite-layer nickelates. Nat. Mater. 19, 381–385 (2020).

    Article  CAS  PubMed  ADS  Google Scholar 

  16. Goodge, B. H. et al. Doping evolution of the Mott-Hubbard landscape in infinite-layer nickelates. Proc. Natl Acad. Sci. USA 118, e2007683118 (2021).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Hayward, M. A., Green, M. A., Rosseinsky, M. J. & Sloan, J. Sodium hydride as a powerful reducing agent for topotactic oxide deintercalation: synthesis and characterization of the nickel(I) oxide LaNiO2. J. Am. Chem. Soc. 121, 8843–8854 (1999).

    Article  CAS  Google Scholar 

  18. Hayward, M. A. & Rosseinsky, M. J. Synthesis of the infinite layer Ni(I) phase NdNiO2+x by low temperature reduction of NdNiO3 with sodium hydride. Solid State Sci. 5, 839–850 (2003).

  19. Wang, B.-X. et al. Synthesis and characterization of bulk Nd1–xSrxNiO2 and Nd1–xSrxNiO3. Phys. Rev. Mater. 4, 084409 (2020).

  20. Greene, R. L., Mandal, P. R., Poniatowski, N. R. & Sarkar, T. The strange metal state of the electron-doped cuprates. Annu. Rev. Condens. Matter Phys. 11, 213–229 (2020).

    Article  CAS  ADS  Google Scholar 

  21. Leonov, I., Skornyakov, S. L. & Savrasov, S. Y. Lifshitz transition and frustration of magnetic moments in infinite-layer NdNiO2 upon hole doping. Phys. Rev. B 101, 241108(R) (2020).

    Article  ADS  Google Scholar 

  22. Li, Y. et al. Impact of cation stoichiometry on the crystalline structure and superconductivity in nickelates. Front. Phys. 9, 719534 (2021).

  23. Gao, Q., Zhao, Y., Zhou, X. J. & Zhu, Z. Preparation of superconducting thin films of infinite-layer nickelate Nd0.8Sr0.2NiO2. Chinese Phys. Lett. 38, 077401 (2021).

  24. Ren, X. et al. Superconductivity in infinite-layer Pr0.8Sr0.2NiO2 films on different substrates. Preprint at https://arxiv.org/abs/2109.05761 (2021).

  25. Ding, X. et al. Stability of superconducting Nd0.8Sr0.2NiO2 thin films. Sci. China-Phys. Mech. Astron. 65, 267411 (2022).

  26. Attfield, J. P., Kharlanov, A. L. & McAllister, J. A. Cation effects in doped La2CuO4 superconductors. Nature 394, 157–159 (1998).

  27. Kim, G. et al. Optical conductivity and superconductivity in highly overdoped La2−xCaxCuO4 thin films. Proc. Natl Acad. Sci. USA 118, e2106170118 (2021).

  28. Guo, Q., Farokhipoor, S., Magén, C., Rivadulla, F. & Noheda, B. Tunable resistivity exponents in the metallic phase of epitaxial nickelates. Nat. Commun. 11, 2949 (2020).

    Article  CAS  PubMed  PubMed Central  ADS  Google Scholar 

  29. Kitatani, M. et al. Nickelate superconductors—a renaissance of the one-band Hubbard model. npj Quantum Mater. 5, 59 (2020).

  30. Nomura, Y. et al. Formation of a two-dimensional single-component correlated electron system and band engineering in the nickelate superconductor NdNiO2. Phys. Rev. B. 100, 205138 (2019).

  31. Zhang, G. M., Yang, Y. F. & Zhang, F. C. Self-doped Mott insulator for parent compounds of nickelate superconductors. Phys. Rev. B. 101, 020501(R) (2020).

    Article  ADS  Google Scholar 

  32. Hsu, Y. T. et al. Insulator-to-metal crossover near the edge of the superconducting dome in Nd1–xSrxNiO2. Phys. Rev. Res. 3, L042015 (2021).

  33. Rossi, M. et al. A broken translational symmetry state in an infinite-layer nickelate. Nat. Phys. 18, 869–873 (2022).

    Article  CAS  Google Scholar 

  34. Krieger, G. et al. Charge and spin order dichotomy in NdNiO2 driven by the capping layer. Phys. Rev. Lett. 129, 027002 (2022).

  35. Tam, C. C. et al. Charge density waves in infinite-layer NdNiO2 nickelates. Nat. Mater. 21, 1116–1120 (2022).

  36. Takagi, H. et al. Systematic evolution of temperature-dependent resistivity in La2–xSrxCuO4. Phys. Rev. Lett. 69, 2975–2978 (1992).

  37. Boebinger, G. S. et al. Insulator-to-metal crossover in the normal state of La2–xSrxCuO4 near optimum doping. Phys. Rev. Lett. 77, 5417–5420 (1996).

  38. Hussey, N. E. Phenomenology of the normal state in-plane transport properties of high-Tc cuprates. J. Phys. Condens. Matter 20, 123201 (2008).

  39. Hwang, H. Y. et al. Scaling of the temperature dependent Hall effect in La2–xSrxCuO4. Phys. Rev. Lett. 72, 2636–2639 (1994).

  40. Fukuzumi, Y., Mizuhashi, K., Takenaka, K. & Uchida, S. Universal superconductor-insulator transition and Tc depression in Zn-substituted high-Tc cuprates in the underdoped regime. Phys. Rev. Lett. 76, 684–687 (1996).

  41. Cooper, R. A. et al. Anomalous criticality in the electrical resistivity of La2–xSrxCuO4. Science 323, 603–607 (2009).

    Article  CAS  PubMed  ADS  Google Scholar 

  42. Bruin, J. A. N., Sakai, H., Perry, R. S. & Mackenzie, A. P. Similarity of scattering rates in metals showing T-linear resistivity. Science 339, 804–807 (2013).

  43. Harvey, S. P. et al. Evidence for nodal superconductivity in infinite-layer nickelates. Preprint at https://arxiv.org/abs/2201.12971 (2022).

  44. Zakharov, A. A., Lazarev, V. B. & Shaplygin, I. S. Interaction of lanthanide sesquioxides with copper and nickel oxide. J. Inorg. Chem. 29, 454–456 (1984).

    Google Scholar 

  45. Aivazov, M. I., Sarkisyan, A. G., Domashnev, I. A. & Gurov, S. V. Synthesis and investigation of compositions in the cross section TiO-NiO. Inorg. Mater. 7, 1389–1391 (1971).

    Google Scholar 

Download references

Acknowledgements

We thank S. Kivelson, T. Devereaux and M. Gabay for useful discussions. This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering (contract no. DE-AC02-76SF00515) and the Gordon and Betty Moore Foundation’s Emergent Phenomena in Quantum Systems Initiative (grant no. GBMF9072, synthesis equipment). C.M. acknowledges support by the Gordon and Betty Moore Foundation’s Emergent Phenomena in Quantum Systems Initiative (grant no. GBMF8686). B.H.G. and L.F.K. acknowledge support by the Department of Defense Air Force Office of Scientific Research (grant no. FA 9550-16-1-0305) and the Packard Foundation. The XRD reciprocal space map measurements were performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation (NSF) under award no. ECCS-2026822. This work made use of a Helios FIB supported by the NSF (grant no. DMR-1539918) and the Cornell Center for Materials Research Shared Facilities, which are supported through the NSF MRSEC programme (grant no. DMR-1719875). The Thermo Fisher Spectra 300 X-CFEG was acquired with support from Platform for the Accelerated Realization, Analysis and Discovery of Interface Materials (PARADIM), an NSF MIP (grant no. DMR-2039380), and Cornell University.

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Authors and Affiliations

Authors

Contributions

K.L. and H.Y.H. conceived the project. K.L. and Y.L. fabricated the polycrystalline targets. K.L. fabricated the perovskite thin films. M.O., Y.L. and W.J.K. performed the soft-chemistry reductions. K.L. conducted XRD characterizations. B.Y.W., T.C.W., Y.L., S.H., W.J.K. and Y.Y. performed the transport measurements. B.H.G. and L.F.K. conducted STEM measurements. K.L., B.Y.W., C.M., S.R. and H.Y.H. wrote the manuscript with input from all authors.

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Correspondence to Kyuho Lee.

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Extended data figures and tables

Extended Data Fig. 1 Analytical mapping of Ruddlesden–Popper faults.

a, Raw HAADF-STEM image of the Nd0.85Sr0.15NiO2 film on SrTiO3 substrate shown in Fig. 1a (left) and a magnified view of the region marked by the red dashed box (right). For the magnified view, atomic overlays are shown to illustrate the half-unit-cell displacement induced by the Ruddlesden-Popper-type stacking faults (RP faults), resulting in the reduced cation contrast. b, Composite of the compressive strain measured on the [101] and [\(\bar{1}\)01] pseudocubic lattice fringes for the HAADF-STEM image in a. The infinite-layer film appears as a region of large compressive strain compared to the substrate because of the shortened c-axis lattice constant. Ruddlesden–Popper type faults in the film are highlighted as regions of local expansion (bright lines) within the film. The highlighted boundaries are used to annotate the vertical Ruddlesden–Popper regions, shown as black (yellow) boxes here (in Fig. 1a). c, Identical strain mapping of the [101] and [\(\bar{1}\)01] pseudocubic lattice fringes for the HAADF-STEM image of the Nd0.85Sr0.15NiO2 film on LSAT substrate (Fig. 1b). The circles in b and c illustrate the coarsening length scale of the Fourier-based analysis. Scale bars, 5 nm.

Extended Data Fig. 2 High-resolution HAADF- and ABF-STEM imaging of Nd0.85Sr0.15NiO2 film on LSAT.

a, High-resolution HAADF- (left) and annular bright-field (ABF)- (right) STEM images of the Nd0.85Sr0.15NiO2 film on LSAT shown in Fig. 1b. Both the lattice size and oxygen column structure visible in the ABF image are consistent with the infinite-layer structure. Atomic model overlays show columns of Nd/Sr (orange), Ni (purple), La/Sr (green), Al/Ta (blue), and O (red). b, HAADF-STEM image of the same Nd0.85Sr0.15NiO2 film on LSAT. c. Quantitative tracking of the local c-axis lattice constant measured between consecutive A-site planes (e.g., Nd to Nd). The lattice constant within the film shows good agreement with the expected value for the infinite-layer structure and the measurements of a fully reduced film by XRD. Scale bars, 5 Å.

Extended Data Fig. 3 X-Ray diffraction of Nd1–xSrxNiO2 on LSAT substrates.

a, Representative XRD θ–2θ symmetric scans of optimized Nd1–xSrxNiO2 (x = 0.05–0.325). The curves are vertically offset for clarity. b, XRD θ–2θ symmetric scan of Nd0.85Sr0.15NiO2 (solid curve) and the corresponding symmetric scan fit (dashed curve). The close agreement in the positions of the main film peak and the Laue fringes indicates a good fit. The asymmetry in the Laue fringes of the film peaks arises from the asymmetric background intensity and the resolution limit of the instrument. The extracted out-of-plane lattice constant c from the fit is labelled. c, c-axis lattice constant versus x for Nd1–xSrxNiO2 films on LSAT (green filled triangles, extracted from a) and on SrTiO3 (red filled circles) using the same growth conditions (Extended Data Table 1). Error bars are the larger of the error in the fit and standard deviation in the values from multiple samples. c increases linearly with x, consistent with systematic doping of Sr in the films. Previous experimental data9,10 on SrTiO3 are also shown as open circles. The substantial elimination of Ruddlesden–Popper-type faults, which locally expand the in-plane lattice11, results in the overall decrease in c compared to previous experimental data. In their absence, the larger c-axis lattice constant in LSAT with respect to SrTiO3 is due to larger compressive strain. Dotted lines are linear fits to the experimental data. dg, Reciprocal space maps of Nd1–xSrxNiO2 films on LSAT for x = 0.075 (d), x = 0.15 (e), x = 0.225 (f), and x = 0.3 (g), showing that the films are fully strained to the LSAT substrate across doping.

Extended Data Fig. 4 Atomic-scale structural characterization by HAADF-STEM of the Nd0.7Sr0.3NiO2 film on LSAT with SrTiO3 capping layer.

HAADF-STEM image of the Nd0.7Sr0.3NiO2 film on LSAT. Scale bar, 5 nm.

Extended Data Fig. 5 Individual resistivity curves of Nd1–xSrxNiO2 on LSAT.

ρ versus T curves of optimized Nd1–xSrxNiO2 films (x = 0.05–0.325). Curves for additional samples at x = 0.075, 0.15, and 0.275 are also shown.

Extended Data Fig. 6 Comparing the Nd1–xSrxNiO2 and the La2–xSrxCuO4 phase diagrams.

Superconducting phase diagram of Nd1–xSrxNiO2 on LSAT (red) and La2–xSrxCuO4 (green), both plotted against the nominal Sr composition x12,36,37,41. The superconducting onset temperature is shown via circles, while the resistive upturn temperature Tupturn is shown as triangles. For La2–xSrxCuO4, the open triangles are Tupturn obtained by suppressing superconductivity with high magnetic field37. The superconducting dome extends from x ≈ 0.1–0.3 (Δx ≈ 0.2) for Nd1–xSrxNiO2 and x ≈ 0.05–0.26 (Δx ≈ 0.21) for La2–xSrxCuO4.

Extended Data Fig. 7 Suppression of superconductivity by magnetic field.

a, ρ versus T of Nd0.825Sr0.175NiO2 film on LSAT under perpendicular magnetic field (0.2–14 T, indicated by color). b, The real (red, left) and imaginary (blue, right) parts of the inductance Lp as a function of T in the pickup coil on a Nd0.825Sr0.175NiO2 film on LSAT, measured using a two-coil mutual-inductance measurement (see Methods).

Extended Data Fig. 8 Individual RH(T) curves of Nd1–xSrxNiO2 on LSAT.

RH versus T curves of optimized Nd1–xSrxNiO2 films (x = 0.05–0.325) on LSAT substrate. RH = 0 is marked as a black dotted line.

Extended Data Fig. 9 Minimal epitaxial strain dependence of Tupturn.

ρ(T) of Nd0.7Sr0.3NiO2 films on SrTiO3 (blue) and LSAT (red), both synthesized using the growth parameters specified in Extended Data Table 1. Prior data of ρ(T) of Nd0.75Sr0.25NiO2 film on SrTiO3 from ref. 9 (yellow dashed curve, see Fig. 2f) is also plotted for comparison. The films on SrTiO3 show considerable suppression of Tupturn (black arrows) upon enhanced crystallinity, with similar order of suppression as the film on LSAT. This suggests that the suppression of the resistive upturn is primarily due to higher film quality, and epitaxial strain plays a sub-dominant role in the resistive upturn.

Extended Data Fig. 10 Cumulative phase diagram of the infinite-layer nickelate Nd1–xSrxNiO2 on LSAT.

The main features of the phase diagram of Nd1–xSrxNiO2 are summarized here. The onset temperature of the superconducting transition Tc,onset is defined as the temperature at which the second derivative of ρ(T) becomes negative, and the 50% transition temperature Tc,50% is defined as the temperature at which ρ is 50% of ρ(Tc,onset). In the underdoped region, ρ shows a resistive upturn, with Tupturn (dark-blue triangles) decreasing as hole doping is increased and superconductivity emerges. Simultaneously, the local maximum in RH (light-blue diamonds) tracks the doping dependence of the resistive Tupturn. Superconductivity emerges at x ≈ 0.1 and persists up to x ≈ 0.3. In the optimal doping of x ≈ 0.15–0.175, the normal-state resistivity shows a linear T-dependence. As superconductivity is suppressed in the overdoped region, T2 resistivity emerges, with a small resistive upturn at low temperatures (dark-blue triangles) driven by disorder. The open circles at the overdoped region delineate the boundary below which the T2 fit shows good agreement with ρ. As x is increased, RH starts to cross zero into positive values (green squares). This transition occurs near the optimal doping, and the zero-crossing temperature increases into the overdoped region.

Extended Data Fig. 11 Powder XRD of polycrystalline target.

Powder XRD of polycrystalline nickelate target with nominal stoichiometry of Nd0.825Sr0.175Ni1.15O3 (red), along with bulk powder XRD of Nd2NiO4 and NiO44,45. Aside from minor shifts in the peak positions due to chemical substitution of Sr, the observed peaks of the target are a superposition of Nd2NiO4 and NiO11.

Extended Data Table 1 Pulsed-laser deposition growth parameters optimized for perovskite Nd1–xSrxNiO3 thin films on LSAT
Extended Data Table 2 Summary of superconducting transition temperatures of Nd1–xSrxNiO2 thin films on LSAT

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Lee, K., Wang, B.Y., Osada, M. et al. Linear-in-temperature resistivity for optimally superconducting (Nd,Sr)NiO2. Nature 619, 288–292 (2023). https://doi.org/10.1038/s41586-023-06129-x

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