2015/05/05 by Zurab Guguchia, A. Amato, Alex Amato +20 · 1 citation
Business, Management and Accounting · Materials Science · Physics and Astronomy · #Condensed matter physics #Corporate Taxation and Avoidance #Hydrostatic pressure #Iron-based superconductors research #Materials science #Muon spin spectroscopy #Pairing #Penetration depth #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Superconductivity #Superfluidity #Thermodynamics #cond-mat.supr-con
paper · pdf · doi:10.1038/ncomms9863
published as Nature Communications 6, 8863 (2015) · 33 pages and 12 figures (including supplementary information)
arxiv created 2015/05/05 · openalex publication_date 2015/11/09 · arxiv updated 2016/03/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The superconducting gap structure in iron-based high-temperature superconductors (Fe-HTSs) is non-universal. In contrast to other unconventional superconductors, in the Fe-HTSs both d-wave and extended s-wave pairing symmetries are close in energy. Probing the proximity between these very different superconducting states and identifying experimental parameters that can tune them is of central interest. Here we report high-pressure muon spin rotation experiments on the temperature-dependent magnetic penetration depth in the optimally doped nodeless s-wave Fe-HTS Ba0.65Rb0.35Fe2As2. Upon pressure, a strong decrease of the penetration depth in the zero-temperature limit is observed, while the superconducting transition temperature remains nearly constant. More importantly, the low-temperature behaviour of the inverse-squared magnetic penetration depth, which is a direct measure of the superfluid density, changes qualitatively from an exponential saturation at zero pressure to a linear-in-temperature behaviour at higher pressures, indicating that hydrostatic pressure promotes the appearance of nodes in the superconducting gap.