Review: Freiburg Infrared Colloquium 2025

On the 18th and 19th of March, the Freiburg Infrared Colloquium (IR-Colloquium) took place at Fraunhofer IAF. The IR-Colloquium is one of the most important conferences in the field of infrared technology and offers experts from science and industry a platform to present the latest developments and results, as well as to discuss future challenges. 

Infrared technology is a key element of modern scientific and industrial applications—from satellite observation to medical diagnostics and military security technology. The IR Colloquium 2025 brought together leading minds from science and industry to present and discuss the latest developments and challenges in the dynamic field of detector and laser technologies.

“Infrared technologies are becoming increasingly important, which is reflected in the growing number of participants at the IR Colloquium. This time, we welcomed 110 participants from 45 organizations and 13 countries. My special thanks go to the speakers for their valuable contributions and to all participants for the intensive interdisciplinary exchange. Once again, the IR Colloquium has provided important impulses for research and industrial applications,” summarizes Dr. Robert Rehm, chairman of the event and head of the business unit Optoelectronics at Fraunhofer IAF.

The latest developments in detectors and lasers

The conference was opened by Matthew Soman from the European Space Agency (ESA), who presented the ESA roadmap for infrared detectors and highlighted future technology requirements. This opening presentation showcased the close links between research and practical applications.

Another highlight was the session on type-II superlattice detectors, where new developments and advances in manufacturing and optimization of the technologies from Sweden, France and the USA were presented. These detectors offer exceptional sensitivity and stability, making them crucial for applications in surveillance and imaging.

In his invited talk, Philip Klipstein from SCD SemiConductor Devices gave an exclusive overview of his company’s 25-year history of MWIR detector technology development.

There has also been impressive progress in the field of emitter technologies. Prof. Dr. Jérôme Faist from ETH Zurich presented new findings on quantum walk effects in quantum cascade laser (QCL) frequency combs. This research could enable novel applications in optical communication and spectroscopy. In addition, developments in the field of gallium-antimonide-(GaSb-)based lasers showed that this technology is increasingly establishing itself as a powerful alternative for high-precision optical systems.

The conference ended with a session on advanced photonics, in which Milos Nedeljkovic from the University of Southampton spoke about mid-IR silicon photonics and Angela Vasanelli from the École Normale Supérieure presented unipolar quantum optoelectronics for mid-infrared free-space communication.

The 46th edition of the IR Colloquium impressively demonstrated how quickly infrared technology is evolving and underscored its role as a driver of innovation in numerous key industries. The next Freiburg Infrared Colloquium will take place on March 16 and 17, 2027.

More information: www.infrared-colloquium.de/