Exploring the effects of Spin Orbit Coupling on the interplay of topology and superconductivity in CaBi2

A new group of materials have recently been identified displaying both superconductivity and topological insulating behaviour, which are of interest in the field of quantum computing. The interplay between superconductivity and topology has yet to be established, making a promising new avenue for research.CaBi2 is proposed to be such a material, with a superconducting transition at 1.95K. Extensive first principles calculations have highlighted the importance of the degree of spin orbit coupling involved to the phonon dispersion and electron-phonon coupling driving the superconductivity. We propose to clarify the significance of it by mapping out the single crystal phonon dispersion, looking at the in-plane Bi modes that are predicted to show a Kohn anomaly in the absence of strong spin orbit coupling.