Proton radiation effect on GaAs/AlGaAs core-shell ensemble nanowires photo-detector

We demonstrate that the GaAs/AlGaAs nanowires (NWs) ensemble is fabricated into photo-detectors. Current-voltage (I-V) characteristics are measured on GaAs/AlGaAs core-shell ensemble NW photo-detectors at room-temperature before and after 1-MeV proton irradiation with fluences from 1.0×10¹³ cm^-2 to 5.0×10¹⁴ cm^-2. The degradation of photocurrent suggests that the point defects induced by proton radiation could cause both carrier lifetime and carrier mobility to decrease synchronously. Comparing with a GaAs quantum well, the degradations of light and dark current for the irradiated NWs photo-detector indicate that NWs material is a preferable potential candidate for space applications.