The family of superconductors that broke the liquid-nitrogen barrier three years ago has a new high-water mark: a nickelate showing superconducting signatures at 100.5 K, the highest ever reported for this class of materials. But the advance reported today in Nature Communications is not just a new number on a temperature ladder. The paper, from a Chinese collaboration spanning Sun Yat-sen University and HPSTAR, argues that a single structural quantity, the distance between the nickel-oxygen layers, acts as a ruler for the whole family: squeeze it, and the superconducting transition temperature rises.
The materials are Ruddlesden-Popper nickelates, layered compounds whose discovery as superconductors in 2023 opened the first credible rival to the cuprates, the ceramics that have dominated high-temperature superconductivity since 1986. In July 2023, La3Ni2O7 crystals compressed to more than 10 GPa (100,000 atmospheres) showed superconducting signatures near 80 K, the first non-cuprate to cross the 77 K boiling point of liquid nitrogen. The new work pushes that frontier further by substituting neodymium for lanthanum, a chemical squeeze that acts like extra pressure.
A lattice that answers to pressure
The team, led by Meng Wang and Hualei Sun at Sun Yat-sen University with Viktor Struzhkin at HPSTAR, synthesized polycrystalline samples of La3-xNdxNi2O7 with x ranging from 0 to 2.4, the highest rare-earth substitution yet achieved in these compounds. Neodymium ions are smaller than lanthanum ions, so each substitution compresses the lattice, most strongly along the axis perpendicular to the nickel-oxygen planes.
The effect on superconductivity is dramatic. Under high pressure, the transport onset of the transition rises from 82 K in the undoped compound to 93 K in La0.9Nd2.1Ni2O7 at 34.9 GPa, and 92 K in the most doped sample at 40.3 GPa. The resistance derivative shows signatures at 96 to 97 K, and a radio-frequency transmission technique, which detects the superconducting response of individual grains, records a clear anomaly at 100.5 K in the x = 2.1 compound at 33 GPa.
The 100.5 K figure is a superconducting signature from the radio-frequency method, not a measurement of zero electrical resistance and not a Meissner effect. The transport data still show residual resistance, which the authors attribute to the polycrystalline nature of the samples and pressure inhomogeneity in the diamond anvil cell. The paper is an unedited early-access manuscript, and the publisher flags that errors may remain before final publication.
The ruler
The paper’s most consequential claim is not the temperature itself but the pattern behind it. Across the whole nickelate family, including ambient-pressure thin films, the maximum transition temperature tracks a single structural parameter: the out-of-plane lattice constant, essentially the spacing between nickel-oxygen bilayers. In the preprint version of the work, the authors quantify the relationship at roughly 28 K of transition temperature per 0.1 nanometer (one angstrom) of interlayer spacing. Near the maximum Tc, all samples, pressurized bulk crystals and thin films alike, fall in a narrow window of lattice parameters.
That correlation is evidence for a specific pairing mechanism. The authors interpret it as enhanced interlayer magnetic exchange: as the layers are pressed together, the magnetic coupling between them strengthens, and that coupling is what glues the superconducting pairs together. Supporting the picture, the magnetic spin-density-wave transition temperature in their samples rises with doping, from 138 K in the undoped compound to 161 K at maximum substitution, signaling stronger magnetic correlations.
The c-axis ruler also gives the field a practical tool. Instead of surveying arbitrary compositions, researchers can use lattice spacing as a design target, a structural descriptor that predicts which chemical substitutions and pressures should push Tc higher. A companion theory paper from the same university predicts maximal transition temperatures near 70 percent neodymium substitution, matching the experimental optimum.
Signatures, not yet a confirmed record
Context matters. The previous nickelate record, reported in Nature in early 2026 with samarium substitution, reached a 96 K onset in the most doped crystals and, more importantly, achieved true zero resistance at 73 K with a measured Meissner effect at 60 K. The new neodymium work reports transport onset around 93 K, nominally below that samarium mark; its genuinely new figure is the 100.5 K radio-frequency signature. The distinction between a precursor-like signature and a bulk superconducting state is exactly where nickelate claims have stumbled before.
Reproducibility is an open question. An independent group at RIKEN reported in a 2026 preprint that it could not reproduce superconductivity in its own neodymium-doped samples up to 20 GPa, seeing only a weak resistance anomaly near 93 K. The field is known to be sensitive to oxygen content and to intergrowths of competing layer structures. The authors acknowledge an anomaly near 10 K in their most doped compound that may stem from such trilayer intergrowths.
What the work establishes, with unusual clarity, is a design principle. Whatever the final verdict on 100.5 K as a superconducting transition, the c-axis correlation holds across pressurized bulk samples and thin films, across lanthanum, samarium, and neodymium substitution. The road past 100 K in nickelates, the paper suggests, runs through the space between the layers, one angstrom at a time.
Sources
1. Zhengyang Qiu, Junfeng Chen, Dmitrii V. Semenok, et al., “High-temperature superconductivity at 100 K in La3-xNdxNi2O7,” Nature Communications (2026), published August 12, 2026. DOI: 10.1038/s41467-026-76534-z. https://www.nature.com/articles/s41467-026-76534-z
2. Preprint (same group): “Interlayer coupling enhanced superconductivity near 100 K in La3-xNdxNi2O7,” arXiv:2510.12359.
3. Previous record: “Bulk superconductivity up to 96 K in pressurized nickelate single crystals,” Nature 649, 871 (2026). DOI: 10.1038/s41586-025-09954-4.
4. Discovery paper: “Signatures of superconductivity near 80 K in a nickelate under high pressure,” Nature 621, 493 (2023). DOI: 10.1038/s41586-023-06408-7.
5. Independent counterpoint: RIKEN preprint arXiv:2604.13875 (no superconductivity observed in La2NdNi2O7 up to 20 GPa).
6. Field review: “Recent progress in nickelate superconductors,” National Science Review (via EurekAlert!, October 2025). https://www.eurekalert.org/news-releases/1103796