  We propose a novel ultrasonic sensor structure composed of Cantilever arm
structure slot dual-micro-ring resonators(DMRR).We present a theoretical
analysis of transmission by using the coupled mode theory.The mode field
distributions and sound pressure distributions of transmission spectrum are
obtained from 3D simulations based on Comsol Multi-physics(COMSOL)method.Our
ultrasonic sensor exhibit theoretical sensitivity as high as 1462.5mV/kPa,which
is 22 times higher than that of single slot-based micro-ring ultrasonic
sensor.Our ultrasonic sensor offers higher sensitivity and a larger detection
frequency range than conventional piezoelectric based ultrasound transducer.The
results show that the sensing characteristics of our system can be optimized
through changing the position and the angle of sound field.Our ultrasonic
sensor with an area of 25um*60um, the-factor can be approximately 1540 with
radius of 5um We detect an angular range of -90o to 90o and a minimum distance
of 0.01um. Finally,we calculate the Cantilever arm structure slot DMRR array
ultrasonic sensor's optical performance. Our proposed design provides a
promising candidate for a hydrophone.
