Thermoelectric Characterization of Electronic Properties of GaMnAs Nanowires

Abstract EN

Nanowires with magnetic doping centers are an exciting candidate for the study of spin physics and proof-of-principle spintronics devices.

The required heavy doping can be expected to have a significant impact on the nanowires' electron transport properties.

Here, we use thermopower and conductance measurements for transport characterization of Ga0.95Mn0.05As nanowires over a broad temperature range.

We determine the carrier type (holes) and concentration and find a sharp increase of the thermopower below temperatures of 120 K that can be qualitatively described by a hopping conduction model.

However, the unusually large thermopower suggests that additional mechanisms must be considered as well.