%0 Journal Article
%T Nodal-to-nodeless superconducting order parameter in LaFeAs1£¿xP x O synthesized under high pressure
%J -
%D 2018
%R https://doi.org/10.1038/s41535-018-0099-y
%X Similar to chemical doping, pressure produces and stabilizes new phases of known materials, whose properties may differ greatly from those of their standard counterparts. Here, by considering a series of LaFeAs1£¿xP x O iron-pnictides synthesized under high-pressure high-temperature conditions, we investigate the simultaneous effects of pressure and isoelectronic doping in the 1111 family. Results of numerous macroscopic and microscopic technique measurements unambiguously show a radically different phase diagram for the pressure-grown materials, characterized by the lack of magnetic order and the persistence of superconductivity across the whole 0.3£¿¡Ü£¿x£¿¡Ü£¿0.7 doping range. This unexpected scenario is accompanied by a branching in the electronic properties across x£¿=£¿0.5, involving both the normal and superconducting phases. Most notably, the superconducting order parameter evolves from nodal (for x£¿<£¿0.5) to nodeless (for x£¿¡Ý£¿0.5), in clear contrast to other 1111 and 122 iron-based materials grown under ambient-pressure conditions
%U https://www.nature.com/articles/s41535-018-0099-y