Highly compact and easy-to-use optical chip interferometer with picometric performances

In this paper, we present a compact, inexpensive, and easy-to-use optical chip interferometer based on the telecom integrated waveguide technology. The measurement evaluation is focused on the resolution and the noise level of the sensor. The power spectral density of 100 fm Hz^-1/2 @ 10 kHz is reached in static conditions. The same level is obtained with the standard Allan deviation for both short and long term measurements. Dynamic performances are also evaluated with sub-nanometer measurements made with piezoelectric systems. The potential bandwidth of the sensor is very high and is currently only limited by electronics (250 kHz).