  Nonlocal tunneling spectroscopy of multiterminal semiconductor-superconductor
hybrid devices is a powerful tool to investigate the Andreev bound states below
the parent superconducting gap. We examine how to exploit both microscopic and
geometrical symmetries of the system to extract information on the normal and
Andreev transmission probabilities from the multiterminal electric or
thermoelectric differential conductance matrix under the assumption of an
electrostatic potential landscape independent of the bias voltages, as well as
the absence of leakage currents. These assumptions lead to several symmetry
relations on the conductance matrix. Next, by considering a numerical model of
a proximitized semiconductor wire with spin-orbit coupling and two normal
contacts at its ends, we show how such symmetries can be used to identify the
direction and relative strength of Rashba versus Dresselhaus spin-orbit
coupling. Finally, we study how a voltage-bias-dependent electrostatic
potential as well as quasiparticle leakage break the derived symmetry relations
and investigate characteristic signatures of these two contributions.
