2023-11-07, Weingartner, Ernest, Bilal, Jonas, Steigmeier, Peter, Jundt, Gregor, Häusler, Samuel, Lenner, Miklós, Flöry, Nikolaus, Bittner, Matthias, Betschon, Felix

Photonic integration on a chip has the potential to develop new low-cost, high-performance sensing devices. A proof of concept of the sensing capabilities of a waveguide-based photothermal interferometer for the measurement of traces of light-absorbing substances (soot particles, gases) has been achieved. The measurement principle can also be extended to a wide range of other applications such as refractive index measurements, or vibration/distance sensors. A unique feature is that the waveguide technology allows for a passive operation of the interferometer, i.e., no quadrature point control is required.