MoS2-based polarization-sensitive photodetectors with asymmetric plasmonic structures and decreased detection time

Abstract

This study analyzes the response time and sensitivity of photosensors that use 2D MoS2 semiconductor films with a high concentration of defects resulting from technological process sequences. In the developed photosensors, we introduce asymmetric plasmonic gratings providing their sensitivity enhancement as well as light polarization sensitivity. The photodetectors, as initially fabricated, exhibit an exceptionally long response time, surpassing a duration of a thousand seconds. This prolonged response time significantly impedes the practical application of these detectors. Nevertheless, the implementation of a specifically designed algorithm enables a dramatic reduction in detection time, by several orders of magnitude in comparison to the response time. It is based on a mathematical model that accounts for the dynamic features of these devices. Our study demonstrates that photodetectors, when enhanced with asymmetric plasmonic gratings, exhibit significantly improved performance metrics. These include a photosensitivity of approximately 60 mA/W and a degree of linear polarization at 0.78. Furthermore, the implementation of our proposed algorithm, which optimizes the calculation of detection time, dramatically reduces the characteristic detection time from over a thousand seconds to just around 10 s.