X-ray induced persistent photoconductivity in Si-doped AlGaAs
arXiv:cond-mat/0007193 · doi:10.1063/1.1410894
Abstract
We demonstrate that X-ray irradiation can be used to induce an insulator-metal transition in Si-doped AlGaAs, a semiconductor with {\it DX} centers. The excitation mechanism of the {\it DX} centers into their shallow donor state was revealed by studying the photoconductance along with fluorescence. The photoconductance as a function of incident X-ray energy exhibits an edge both at the Ga and As K-edge, implying that core-hole excitation of Ga and As are efficient primary steps for the excitation of {\it DX} centers. A high quantum yield () suggests that the excitation is indirect and nonlocal, due to secondary electrons, holes, and fluorescence photons.
3 pages of text, 6 figures. An error in Fig.5 was detected, so we corrected it