Meservey-Tedrow-Fulde effect in a quantum dot embedded between metallic and superconducting electrodes

Magnetic field applied to the quantum dot coupled between one metallic and one superconducting electrode can produce a similar effect as has been experimentally observed by Meservey et al. Phys. Rev. Lett. 25 1270 (1970)] for the planar normal metal-superconductor junctions. We investigate the tunneling current and show that indeed the square-root singularities of differential conductance exhibit the Zeeman splitting near the gap-edge features V=±Δ/e. Since magnetic field affects also the in-gap states of quantum dot, it furthermore imposes a hyperfine structure on the anomalous (subgap) Andreev current which has a crucial importance for a signature of the Kondo resonance.