Sensors are the heart of every smart technology. Due to a plethora of vibrational and rotational resonances throughout a multitude of fluids, the infrared is the spectral region of choice, when it comes to sensing and spectroscopy. Quantum Cascade Lasers and Interband Cascade Lasers as well as Semiconductor Frequency Combs and Detectors are the key components for performing infrared spectroscopy with compact and versatile devices. The ability to select the laser wavelength by modification of the heterostructure design facilitates tailor-made applications.

On-chip systems

Reducing the size and weight of those sensors enables unprecedented applications across a variety of fields such as chemical gas analysis for environmental monitoring to medical breath inspection of specific biomarkers for cancer identification. We develop novel monolithic sensors, based on bi-functional QCLD designs. Bi-functionality allows mid-IR devices to emit and detect coherent light at the same wavelength, opening the pathway towards fully integrated on-chip solutions. This not only opens the possibility for large scale batch processing but also enables the fabrication of compact and battery driven components that could be implemented in hand-held devices such as our smartphone. Furthermore, they enable the implementation of microfluidic cells down to the chip-level or live monitoring of chemical reactions or structural changes in liquids.