  Hybrid nanostructures consisting of two parallel InAs nanowires connected by
an epitaxially grown superconductor (SC) shell recently became available. Due
to the defect-free SC-semiconductor interface and the two quasi-one-dimensional
channels being close by, these novel platforms can be utilized to spatially
separate entangled pairs of electrons by using quantum dots (QD) in the
so-called Cooper pair splitting (CPS) process. The minimized distance between
the QDs overcomes the limitations of single-wire-based geometries and can boost
the splitting efficiency. Here we investigate CPS in such a device, for the
first time, where strong inter-dot Coulomb repulsion is also present and
studied thoroughly. We analyze theoretically the slight reduction of the CPS
efficiency imposed by the Coulomb interaction and compare it to the
experiments. Despite the competition between crossed Andreev reflection (CAR)
and inter-wire capacitance, a significant CPS signal is observed indicating the
dominance of the superconducting coupling. Our results demonstrate that the
application of parallel InAs nanowires with epitaxial SC is a promising route
for the realization of parafermionic states relying on enhanced CAR between the
wires.
