Our laboratory is located in the Department of Physics of the University of Basel in Switzerland. Our research is centered around the emerging field of "Quantum sensing", where the use of individual, well-controlled quantum systems as high-performance sensing devices is being explored. We concentrate on implementing various types of such sensors and on applying them to outstanding scientific tasks in mesoscopic physics, nano-science and technology. At the moment, our quantum system of choice for these purposes is the Nitrogen-Vacancy (NV) color center in diamond, whose exceptional quantum-coherent properties allow for high-performance sensing applications (such as single-electron spin detection) even at room temperature.
Daniels's paper "Deterministic enhancement of coherent photon generation from a nitrogen-vacancy center in ultrapure diamond" was published in PRX. We couple NV centers to a tunable microcavity and significantly enhance their photonic properties: i.e. we demonstrate an increase of the phonon-free emission--which is required for entanglement swapping schemes--from 4% to close to 50%. By making a step-change in the NV's optical properties in a deterministic way, these results pave the way for much enhanced spin-photon and spin-spin entanglement rates.
Arne Barfuss has won the Swiss Nanotechnology Award sponsored by Rolic Technologies Ltd. for the outstanding publication "Strong mechanical driving of a single electron spin". For the first time, the Swiss MNT Network presents this award to doctoral students at the Swiss research center. Congrats Arne!
Jean and Arne's paper "Hybrid continuous dynamical decoupling: a photon-phonon doubly dressed spin" studies parametric interaction between a single Nitrogen-Vacancy electronic spin and a diamond mechanical resonator. We present a novel dynamical decoupling scheme, which is based on recently established techniques for dynamical decoupling by concatenated continuous driving. Our work benefits from a robust, drift-free strain-coupling mechanism we have established in the past and from the narrow linewidth of the high-quality diamond mechanical oscillator we employ. We demonstrate prolongation of the relevant spin dephasing times by up to two orders of magnitude, suggesting feasible applications of our decoupling scheme in quantum information processing and sensing.