We present an optically-detected mechanical accelerometer that achieves a sensitivity of 100 ng/rtHz over a bandwidth of 10kHz and is traceable. We have incorporated a Fabry-Perot fiber-optic micro-cavity that is currently capable of measuring the test-mass displacement with sensitivities of 200 am/rtHz, and whose length determination enables traceability to the International System of Units (SI). The compact size and high mQ-product achieved combined with the high sensitivity and simplicity of the implemented optical detection scheme highlight our device and this category of accelerometers, outlining a path for high sensitivity reference acceleration measurements and observations in seismology and gravimetry

We present an optomechanical accelerometer with high dynamic range, high bandwidth and readout noise levels below 8 µg/ √ Hz . The straightforward assembly and low cost of our device make it a prime candidate for on-site reference calibrations and autonomous navigation. We present experimental data taken with a vacuum sealed, portable prototype and deduce the achieved bias stability and scale factor accuracy. Additionally, we present a comprehensive model of the device physics that we use to analyze the fundamental noise sources and accuracy limitations of such devices.