TIME-RESOLVED OPTICAL BEAM-INDUCED CURRENTS - A NOVEL TECHNIQUE TO IMAGE SPATIOTEMPORAL PHENOMENA IN SEMICONDUCTORS

The technique of optical beam induced currents is widely used to study electrical transport in semiconductors. We extend this technique to a chieve time resolved measurements. As a demonstration of the power of this TROBIC technique we apply this technique to study the electrical transport properties of a two-dimensional electron gas in an AlxGa1-xA s/GaAs (HEMT) heterostructure subjected to high electric fields. Image s are presented recorded by this technique showing current filamentati on in the semiconductor heterostructure spreading as a function of tim e.