Executive Summary : | Stochastic Resonance (SR) is a counter-intuitive phenomenon, wherein the detection of weak periodic signals by systems with an inherent threshold or energetic bistability, improves with the addition of an optimal amount of noise. It was first proposed by Benzi et al. to explain the quasi-periodic variation in atmospheric temperature over large time periods. SR is also thought to play a role in the nervous systems of crayfish and paddlefish, resulting in its importance in neurobiological research Recently, several engineering applications of SR have emerged. These applications are based on devices/systems that have a detection threshold. Addition of the optimum noise causes the weak input to cross the threshold, thereby enabling detection. Devices/systems with bistable behaviour can demonstrate more robust SR. Ferroelectric materials possess an inherent bistable energy landscape, and hence should be interesting candidates to realize SR based detectors. In the early 2000s, Drozhdin reported preliminary experimental results on SR in bulk Triglycine Sulphate (TGS) crystals, by tracking the polarization of the ferroelectric in the presence of noise. Practical applications using bulk ferroelectrics are difficult owing to the setup needed to measure the polarization. In this work, we seek to study the possibility of SR in devices having thin-film integrated ferroelectrics. This proposal builds on our earlier work which investigated the possibility of SR in thin film HfZrO2 capacitors using numerical simulations and analytical calculations. In this work, we propose integrating thin film ferroelectric Polyvinylidene fluoride (PVDF) as the insulating material of a Graphene transistor. We choose PVDF due to the possibility of fabrication of high-quality ferroelectric PVDF films using low-cost spin-coating and Langmuir-Blodgett deposition. The transistor configuration should enable a direct readout of the polarization of the ferroelectric. We also propose an application of this SR transistor to detect weak and noisyFrequency Shift Keying (FSK) signals. The extra noise that needs to be added for optimum signal detection depends on the amount of noise inherently present in the signal. Such a system could find use in high-noise environments such as underwater visible light communication. |