The ImPhys team with Fellipe Peternella, Boling Ouyang, Roland Horsten and Jacob Caro, together with the Dutch company Technobis tft-fos, published an interrogation procedure of a ring-resonatr ultrasound sensor in Optics Express.

The team demonstrates the interrogation procedure using a fiber Mach-Zehnder interferometer (MZI). The sensor is based on a silicon ring resonator located on a thin membrane, that has its lowest vibrational mode in the MHz range. This is the range used in medical ultrasound imaging. Ultrasound incident on the membrane excites its vibrational mode, resulting in a modulation of the optical resonance wavelength of the ring resonator. The modulation signal is detected with the MZI, according to the interrogation procedure developed. The interrogation leads to an output signal of the MZI proportional to the ultrasound pressure and can be applied to a wide range of pressures. This work with the fiber MZI is an important step towards an integrated photonics interrogator, which has the capability of reading out an array of ultrasound sensors as used in medical imaging.

The article can be read here.