Magnetic impurity in hybrid and type-II nodal line semimetals

We study the Kondo screening of a spin-1/2 magnetic impurity in the hybrid nodal line semimetals (NLSMs) and the type-II NLSMs by using the variational method. We mainly study the binding energy and the spin-spin correlation between magnetic impurity and conduction electrons. We find that in both the hybrid and type-II cases, the density of states (DOS) is always finite, so the impurity and the conduction electrons always form bound states, and the bound state is more easily formed when the DOS is large. Meanwhile, due to the unique dispersion relation and the spin-orbit couplings in the NLSMs, the spatial spin-spin correlation components show very interesting features. Most saliently, various components of the spatial spin-spin correlation function decay with 1/r2 in the hybrid NLSMs, while they follow 1/r3 decay in the type-II NLSMs. This property is mainly caused by the special band structures in the NLSMs, and it can work as a fingerprint to distinguish the two types of NLSMs.