The physics of the Kagome metal LaRh3B2 along with its superconductivity below 2.6 K, unlike other popular Kagome metals, is not known to be significantly influenced by the electron correlations. While the indirect techniques to probe the bulk superconducting properties of LaRh3B2 indicate a conventional isotropic order parameter, we show that the direct spectroscopic determination of the superconducting energy gap reveals an anomalous suppression of Andreev reflection between LaRh3B2 and a normal metal. This observation hints to the presence of incomplete superconducting gap formation, at least along certain momentum directions, and consequent low-lying quasiparticle states. An analysis of multiple Andreev reflection spectra captured at different points on the surface of LaRh3B2 reveals a distribution of the superconducting energy gap which is consistent with an anisotropic superconducting order parameter.
Garg et al. (Mon,) studied this question.