As the physical dimensions of the building blocks in electronics and optics shrink, quantum mechanical effects become increasingly important. We explore applications of quantum systems in electronics, optics and information technology. Some specific areas we have researched in this respect are microlasers, fibre-optical communication systems, optical amplifiers, quantum cryptography and optical and atomic interferometry. In addition we try to improve our understanding of fundamental quantum physics. Some examples of such research include complementarity, measurement back-action, simultaneous measurements and the physical representation of information.

Highlights

• Demonstration of antibunching from InAs quantum dots
• Demonstration of an "interaction-free" measurement
• Quantum cryptography over 40 km of optical fibre
• Heisenberg-limited interferometry
• Demonstration of quantum erasure
• Microcapillary flow-velocity profiling through correlation spectroscopy
• Demonstration of nonlocality of a single photon