Research Track Leaders: Dr. Simone Ferrari and Dr. Anna Ovvyan.
Our subgroup investigates low-temperature photonics and waveguide-integrated superconducting nanowire single-photon detectors, with an emphasis on experimental device development, cryogenic characterization, and system integration.
A major research focus is the development of superconducting nanowire detectors directly integrated with optical waveguides. We study these devices from both fundamental and application-oriented perspectives, examining how material properties, device geometry, optical coupling, and cryogenic operating conditions influence their performance. This knowledge is then used to design detectors adapted to more complex photonic circuits and measurement systems.
Our work spans the full experimental process, from superconducting and optical materials to fabricated devices and complete measurement platforms. It includes the characterization of thin superconducting films, their integration with different photonic material platforms, the development of nanofabrication processes, device design, cryogenic packaging, optical coupling, and low-noise electrical readout.
Particular attention is devoted to the interface between superconducting detectors and integrated photonic circuits. At this interface, optical absorption, detection efficiency, timing resolution, device yield, and scalability must be considered together rather than optimized independently.
In addition to individual detectors, we work on detector arrays, photon-number-resolving architectures, and cryogenic optoelectronic circuits. These systems require not only optimized detector geometries, but also reliable readout architectures and measurement techniques compatible with low-temperature operation. We therefore develop and continuously improve cryogenic experimental setups, measurement procedures, and readout concepts for superconducting photonic devices.
The broader goal of the subgroup is to advance detector technologies and cryogenic photonic platforms for future quantum and classical optical systems. Potential applications include quantum communication, quantum key distribution, photonic quantum computing, optical metrology, and advanced imaging.
By combining materials research, nanofabrication, integrated photonics, and cryogenic measurements, we aim to understand both the physical limits and the technological opportunities of superconducting detectors. This allows us to translate fundamental insights into practical concepts for devices, circuits, and measurement systems.
Our research is embedded in a wider network of activities in photon detection and integrated photonics. Through collaborations with academic institutes, start-ups, and industrial partners, we connect fundamental device research with practical challenges in scalable fabrication, packaging, system integration, and real-world applications.
