New Type of Magnetic Sensor Based on Stochastic Resonance in a Flux Quantized Superconducting Loop

We have recently demonstrated stochastic resonance in a superconducting loop containing two Josephson junction, coupled to a conventional Superconducting Quantum Interference Device (SQUID). We now propose to create a new type of magnetic sensor in which a stochastically resonating superconducting system, acts as preamplifier for a conventional SQUID. Our proposed work will take advantage of the increase in signal to noise ratio and noise tolerance exhibited by the stochastic resonance effect to significantly improve SQUID based magnetic detection. In Phase I, we will demonstrate these enhancements in a laboratory prototype made from discrete components and provide a preliminary design for an optimized sensor. In Phase II, we will fabricate a complete, integrated sensor in high-Tc superconducting materials. The system will be a portable, stand alone unit and contain all necessary support electronics. Extensive field tests will be performed.