Selective mass enhancement close to the quantum critical point in BaFe₂(As_1-x P _x )₂.

ABSTRACT: A quantum critical point (QCP) is currently being conjectured for the BaFe₂(As_1-x P _x )₂ system at the critical value x _c  ≈ 0.3. In the proximity of a QCP, all thermodynamic and transport properties are expected to scale with a single characteristic energy, given by the quantum fluctuations. Such a universal behavior has not, however, been found in the superconducting upper critical field H _c2. Here we report H _c2 data for epitaxial thin films extracted from the electrical resistance measured in very high magnetic fields up to 67 Tesla. Using a multi-band analysis we find that H _c2 is sensitive to the QCP, implying a significant charge carrier effective mass enhancement at the doping-induced QCP that i

SUBMITTER: Grinenko V 

PROVIDER: S-EPMC5496881 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature