Humboldt-Universität zu Berlin - Faculty of Mathematics and Natural Sciences - Fundamentals of Optics and Photonics

Introduction

Glass fibers play an important role for guiding and controlling light in many areas of everyday life: Owing to their enormous capacity for data transmission, they have become the backbone of the modern information society. Moreover, they have numerous applications in medicine and industry. However, despite the widespread and successful use of glass fiber technology, the design and optimization of novel types of glass fibers is still a highly active field of research which yielded impressive progress recently. As an example, so-called “photonic fibers” could overcome a number of restrictions limiting conventional fiber optics. This development opened technological and scientific routes which gave new stimuli to research with and on optical fibers and initiated a race venturing ever more extreme fields of application using glass fibers.

In this context, we enter the regime of quantum physics employing specially designed glass fibres. More precisely, we quantum mechanically couple light and matter (atoms, molecules, etc.) on the surface of ultra-thin glass fibers. Depending on the application, the diameter of the glass fibers ranges from a few ten micrometres down to a few hundred nanometres, using the strong spatial confinement of the light for an extreme focusing which enhances the light–matter interaction. Such a strong coupling of light and matter based on glass fibers opens a number of perspectives. Potential applications include the ultra-high sensitivity detection of molecules, chemical and biological nano-sensing, “atomic switches” for light fields, and novel types of light sources, required for quantum communication, quantum cryptography, and for quantum information processing.

A more detailed introductory article (only available in German) can be found here.