Welcome to the quantum optics lab
We explore fundamental quantum physics with atoms, photons and phonons and harness it for applications in quantum technology. In our experiments we study many-particle entanglement in Bose-Einstein condensates, explore hybrid atom-optomechanical systems, and develop quantum memories and sensors with atomic vapour cells. Our research combines experiment with theory, employing techniques of atomic physics, quantum optics and optomechanics. A common goal of our activities is to investigate quantum physics in systems of increasing size and complexity.
News from the lab
Einstein-Podolsky-Rosen Experiment with two Bose-Einstein condensates
We observed the Einstein-Podolsky-Rosen paradox with two spatially separated, massive many-particle systems. Our results show that the conflict between quantum mechanics and local realism does not disappear as the system size increases to…
Optical Coherent Feedback Control of a Mechanical Oscillator
Coherent feedback is a kind of feedback that processes and feeds back quantum signals without measuring the system. We implemented a coherent feedback loop consisting of a light field interacting twice with the same mechanical mode of a…
Maryse and Paolo Receive QCQT Excellence Awards
Congratulations to Maryse Ernzer and Paolo Colciaghi! Both of their 2022 research has been recognized with QCQT excellence awards.
Thomas Karg wins SPS Award
Each year, the Swiss Physical Society awards topical prizes for exceptional PhD thesis. We congratulate Thomas Karg on winning this year's Metrology award, sponsored by METAS, for his work on the strong coupling of a nanomechanical…
Single-Photon Storage in a Ground-State Vapor Cell Quantum Memory
Storing single photons from solid state sources in hot atomic vapor has been a long standing challenge due to read-out noise produced by the atoms. With a storage scheme exploiting polarization selection rules we have succeded in storing…
Coherent Feedback Cooling of a Nanomechanical Membrane with Atomic Spins
Coherent feedback stabilises a system towards a target state without the need of a measurement, thus avoiding the quantum backaction inherent to measurements. In our experiment, we employ optical coherent feedback to remotely cool a…Thomas Karg wins Swiss Nanotechnology PhD Award
The Swiss Nanotechnology PhD Award is given by the Swiss Micro‐ and Nanotechnology Network for excellent scientific first‐author publications in the field of Nanotechnology and Nanoscience published by PhD students. Thomas Karg received the…
Light-mediated strong coupling between a mechanical oscillator and atomic spins one meter apart
Engineering strong Hamiltonian interactions between quantum systems is usually only possible over short distances. We demonstrate a new scheme for long-distance interactions mediated by light and use it for a range of experiments in hybrid…
Basel Quantum Metrology and Sensing Conference
The Basel Quantum Metrology and Sensing Conference (BQMS 2020) will highlight the state of the art and most recent advances in quantum sensing and quantum metrology with atomic and solid-state spin systems. It will gather key global players…