  Nonlocal quasiparticle transport in normal-superconductor-normal (NSN) hybrid
structures probes sub-gap states in the proximity region and is especially
attractive in the context of Majorana research. Conductance measurement
provides only partial information about nonlocal response composed from both
electron-like and hole-like quasiparticle excitations. In this work, we show
how a nonlocal shot noise measurement delivers a missing puzzle piece in NSN
InAs nanowire-based devices. We demonstrate that in a trivial superconducting
phase quasiparticle response is practically charge-neutral, dominated by the
heat transport component with a thermal conductance being on the order of
conductance quantum. This is qualitatively explained by numerous Andreev
reflections of a diffusing quasiparticle, that makes its charge completely
uncertain. Consistently, strong fluctuations and sign reversal are observed in
the sub-gap nonlocal conductance, including occasional Andreev rectification
signals. Our results prove conductance and noise as complementary measurements
to characterize quasiparticle transport in superconducting proximity devices.
