Quasiparticle interference in heavy fermion superconductors. Role of the slab geometry

We analyze theoretically the quasiparticle interference in the heavy fermion superconductors CeCoIn₅ and UPt₃ as a direct method to investigate the gap symmetry. In contrast to the prior attempts that computed QPI patterns for some effective two-dimensional models or by performing calculations for various k_z cuts and then averaging the final result, we perfom the calculations for the three-dimensional models in the slab geometry and investigate possible effects of the finite sample size, topology, and surface termination. Comparing with the results of prior analysis of the bulk system we can conclude on the importance of the possible surface states for determining the QPI pattern.