Utilization of self-assembled AuGe nanoparticles for improving performance of InGaAs/GaAs quantum dot infrared detector

We report the successful realization of a plasmonic-based heptalayer self-assembled InGaAs quantum-dot infrared photodetector (QDIP) using self-assembled AuGe nanoparticles. In comparison with as-grown device, AuGe detector showed a 30% increase in spectral response at a peak of similar to 5 mu m and -1 V bias. We achieved two-order increment in peak responsivity of AuGe plasmonic-based detector in comparison to as-grown detector at 80 K. The improvements are attributed to increased light trapping in the device and strong plasmonic-QD interaction by the AuGe nanoparticles. In this technique, AuGe nanoparticles are self-assembled; therefore they don't require very fine optical or e-beam lithography for patterning, indicating this technique will be helpful in reducing the cost of plasmonic based high-performance detectors.