Parallel operation and crosstalk measurements in GaAs étalon optical logic devices

We report the first parallel operation of GaAs optical logic elements and bistable devices. Arrays up to 2×4 in size were operated using a picosecond pump and probe technique, while in the bistable mode we achieved uniform response in two spots. Crosstalk due to carrier diffusion became noticeable at separations of typically ∼20–30 μm in the bistable devices. Pulsed operation at 82 MHz allowed separations down to ∼10 μm limited only by diffraction. Efficient heat sinking in the pulsed array resulted in negligible heating even when continually operated for many minutes. All experiments were performed at room temperature.