fiber sensors, underwater acoustics, biophotonics.I. INTRODUCTION
Hydrophones are widely used in aquatic environments for acoustic detection, exploration, and communication [1]-[5].However, the highest resolu- tion optical hydrophones use externally-mounted Fabry-Perot interferometric cavities [1], [2], [4], [6], [9], [10], [18]
Intracellular electrical measurements are used in study- ing cell electrophysiology for a variety of applications [19]-[21].Common optical hydrophones include Bragg-gratings [14], fiber-lasers [15], Mach-Zender interferometers [16], and Sagnac interferometers [17].For