A gallium interstitial defect is thought to be responsible for the spectacular spin-dependent recombination in ${\mathrm{GaAs}}_{1-x}{\mathrm{N}}_x$ dilute nitrides. Current understanding associates this defect with at least two in-gap levels corresponding to the ($+/0$) and ($++/+$) charge-state transitions. Using a spin-sensitive photoinduced current transient spectroscopy, the in-gap electronic structure of a $x=0.021$ alloy is revealed. The ($+/0$) state lies $\approx 0.27\mathrm{eV}$ below the conduction band edge, and an anomalous, negative activation energy reveals the presence of not one but two other in-gap states. The observations are consistent with a ($++/+$) state $\approx 0.19\mathrm{eV}$ above the valence band edge, and a ($+++/++$) state $\approx 25\mathrm{meV}$ above the valence band edge.

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• Carrier generation & recombination
• Defects
• Electronic structure
• Interstitials
• Photocurrent
• Spin dynamics
• Spin filtering
• Deep level transient spectroscopy