  In this paper we present our progress towards the opto-electronic
characterization of indium phosphide (InP) nanowire transistors at milli-Kelvin
(mK) temperatures. First, we have investigated the electronic transport of the
InP nanowires by current-voltage (I-V) spectroscopy as a function of
temperature from 300 K down to 40 K. Second, we show the successful operation
of a red light emitting diode (LED) at liquid-Helium (and base) temperature to
be used for opto-electronic device characterization.
