Speaker
Description
Non-centrosymmetric superconducting materials represent an exciting class of novel superconductors featuring a variety of unconventional properties, including mixed-parity pairing and very high upper critical fields. Here, we present a comprehensive study of TaIr$_2$B$_2$ (with $T_c = 5.1$ K), using a set of complementary experimental methods, including bulk- and surface-sensitive techniques. We provide evidence that this system is a two-band, yet it behaves as a single-gap superconductor with a strong coupling. The upper critical field of TaIr$_2$B$_2$ significantly exceeds the Pauli limit and exhibits a nearly linear temperature dependence down to the lowest temperatures. This behavior, rarely seen in superconductors, is discussed in terms of anti-symmetric spin-orbit interaction, two-band-, and strong-coupling effects, as well as disorder.
Acknowledgements
The work at Gdansk University of Technology was supported by the National Science Center (Poland), Grant No. 2022/45/B/ST5/03916. The work at Slovak Academy of Sciences was supported by Projects APVV-23–0624, VEGA 2/0073/24, COST Action No. CA21144 (SUPERQUMAP), Slovak Academy of Sciences Project IMPULZ IM-2021–42. We acknowledge the support of LNCMI-CNRS, member the European Magnetic Field Laboratory (EMFL). 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-1644779 and the State of Florida.
