The observation of π-shifts in the Little-Parks effect in 4Hb-TaS<sub>2</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38816364.
- Also identified by DOI 10.1038/s41467-024-48260-x and PMC identifier 11139670.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Finding evidence of non-trivial pairing states is one of the greatest experimental challenges in the field of unconventional superconductivity. Such evidence requires phase-sensitive probes susceptible to the internal structure of the order parameter. We report the measurement of the Little-Parks effect in the unconventional superconductor candidate 4Hb-TaS<sub>2</sub>. In half of our rings, which are fabricated from single-crystals, we find a π-shift in the transition-temperature oscillations. According to theory, such a π-shift is only possible if the order parameter is non-s-wave. In the absence of crystallographic defects, the shift provides evidence of a multi-component order parameter. Thus, this observation increases the likelihood of the two-component order parameter scenario in 4Hb-TaS<sub>2</sub>. Furthermore, we show that T<sub>c</sub> is enhanced as a function of the out-of-plane field when a constant in-plane field is applied, which we explain using a two-component order-parameter.