EFFECT OF NEUTRON-IRRADIATION ON TRANSPORT IN HETEROSTRUCTURES

The effects of fast (E(n) = 14 MeV) and thermal (E(n) = 0.025 eV) neutron irradiation on quantum transport in modulation-doped heterostructures and double barrier resonant tunneling diodes have been investigated. In the case of modulation doped heterostructures, both concentration and mobility of the 2DEG at 4.2 K decreased in the dark after fast neutron irradiation. The Hall plateau broadened and the SdH oscillation was clearly enhanced under high magnetic fields. The increase of the concentration and mobility of 2DEG, Hall plateau broadening and SdH oscillation enhancing as well as parallel conductance were observed at 4.2 K in samples irradiated by thermal neutrons. All the changes disappeared gradually with time. In double barrier resonant tunneling structures irradiated by fast neutrons, the peak current position V(p), valley current I(p) and peak-to-valley ratio (PTVR) decreased.