  The proximity-induced superconducting state in the 3-dimensional topological
insulator HgTe has been studied using electronic transport of a normal
metal-superconducting point contact as a spectroscopic tool (Andreev point
contact spectroscopy). By analyzing the conductance as a function of voltage
for various temperatures, magnetic fields and gate-voltages, we find evidence,
in equilibrium, for an induced order parameter in HgTe of $70\,\mu$eV and a
niobium order parameter of $1.1\,$meV. To understand the full conductance curve
as a function of applied voltage we suggest a non-equilibrium driven
transformation of the quantum transport process where the relevant scattering
region and equilibrium reservoirs change with voltage. This implies that the
spectroscopy probes the superconducting correlations at different positions in
the sample, depending on the bias voltage.

Mesoscale and Nanoscale Physics;Superconductivity