Electro-optic voltage profiling of modulation-doped GaAs/AlGaAs heterostructures

Abstract
The electro‐optic effect of GaAs is applied to profile the voltage distribution of the two‐dimensional electron gas (2DEG) in a GaAs/AlGaAs heterostructure. In our setup we reached a voltage sensitivity of 2 mV. We used this technique to characterize the local resistivity of the 2DEG. The results are consistent with those obtained from scanning electron microscopy voltage contrast measurements.