"Anisotropic Superconducting Gap in Optimally Doped Iron–Based Material"

A. Pal: M. Chinotti, J.-H. Chu, H.-H. Kuo, I. R. Fisher, L. Degiorg; Journal of Superconductivity and Novel Magnetism, 12/17/19.

Additional Authors: M. Chinotti, J.-H. Chu, H.-H. Kuo, I. R. Fisher, L. Degiorg

Abstract:

We offer a comprehensive optical investigation of the optimally hole-doped Ba0.6K0.4Fe2As2 over a broad spectral range, as a function of temperature and of tunable applied stress, which acts as an external symmetry breaking field. We show that there is a large electronic nematicity at optimal doping which extends right under the superconducting dome and implies an anisotropy of the superconducting energy gaps.