Comprehensive Analog Signal Processing Platform Enabled with Acoustic Charge Transport in Two-dimensional Materials

Abstract

Two-dimensional Acoustic Charge Transport (2D-ACT) devices, which integrate two dimensional semiconductor field-effect transistor (FET) with high-frequency surface acoustic wave (SAW) device provide a potential compact platform for the processing of analog signals in a wireless, non-contact, low-loss and real-time way. It is expected to be used in long-distance space communication and sensing. However, current investigations into 2D-ACT devices are still limited to the observation of DC acoustoelectric currents, and have yet to achieve real-time electronic signal processing capabilities. In this paper, we have designed a hybrid acoustoelectric platform composed of two-dimensional semiconductor FET and SAW device. The platform is capable of processing DC signals, exhibiting ambipolar transport behavior. The sub-wavelength channel length of the FET within the platform allows for the real-time observation of carrier distribution at a microscopic scale in conjunction with the SAW potential, and facilitating the reproduction and intensity regulation of AC signals. By adjusting the relative phase and intensity ratio of two counter-propagating SAWs, the platform also enables the addition and subtraction of AC signals.