Quantum Physics

ETH Professor Klaus Ensslin spent 12 years at the helm of the National Centre of Competence in Research “Quantum Science and Technology”. As the programme prepares to wind down at the end of this year, we spoke to him about scientific breakthroughs and Switzerland’s role in quantum research.

For the first time, ETH Zurich researchers have been able to make a superconducting component from graphene that is quantum coherent and sensitive to magnetic fields. This step opens up interesting prospects for fundamental research.

Physicists at EPFL have developed a formulation to solve the longstanding problem of electron self-interaction when studying polarons – quasiparticles produced by electron-phonon interactions in materials. The work can lead to unprecedented calculations of polarons in large systems, systematic studies of large sets of materials, and molecular dynamics evolving over long time periods.

Scientists from EPFL, the Max Planck Institute for Multidisciplinary Sciences and the University of Göttingen have successfully created electron-photon pairs for the first time in a controlled way, using integrated photonic circuits on a chip. Using a new technique, they could precisely detect the involved particles. The findings of the study expand the toolbox of quantum technology.

A method known as quantum key distribution has long held the promise of communication security not possible in conventional cryptography. For the first time, an international team of scientists, including researchers from EPFL, has demonstrated experimentally an approach to quantum key distribution based on high-quality quantum entanglement — offering much broader security guarantees than previous schemes.