Developing Highly Sensitive SAW Standing Wave Magnetic Sensor through Resonant Frequency Shift and Acoustic Energy Concentration

This study focuses on the design and optimization of Surface Acoustic Wave (SAW) magnetic field sensors. We designed and fabricated a SAW standing wave magnetic sensor, successfully enhancing its sensitivity by exploiting both the equivalent acoustic velocity variation induced by the ΔG effect of magnetostrictive materials and the concentration effect of acoustic energy. The experimental results reveal a linear enhancement in sensor sensitivity correlated with the increasing input voltage, peaking at 0.67 mV/Oe under a 1 V input. This design breakthrough introduces novel possibilities for magnetic field detection technology, providing fresh insights and design pathways for the advancement of high-sensitivity magnetic field sensors.