Hybrid Quantum Optics
This picture shows the probe and control light used for Rydberg excitation as of 2024.
Int he picture you can see a Magneto-optical trap with 10 9 Rubidium atoms trapped in our chamber which are later transported to the region where the experiment will be conducted.
First atom chip design (left) and fabricated atom chip (right) which will be used to trap the atoms on a wire-trap on a chip and interface rubidium Rydberg atoms with the microwave waveguide resonator on the chip.
The Hybrid Quantum Optics (HQO) project combines nonlinear quantum optics based on the strong interactions between atomic Rydberg excitations with integrated photonics and optomechanical systems. Based on the former, a large variety of single-photon devices has been demonstrated over the last decade, for example single-photon sources, optical transistors and switches, single photon subtractors, and quantum gates for optical qubits. Building on our experience from the RQO project, we are now aiming to realize such quantum devices on photonic chips for example to implement cascaded quantum systems devices or to achieve coherent optical readout of neutral-atom qubit arrays.
For this purpose, we are constructing a new and innovative cryogenic ultracold atom apparatus that will allow us to trap and manipulate atoms near integrated photonic chips cooled to 4 K. Besides the reduction of thermally induced noise, the improved vacuum conditions will allow for rapid changes to the experiment, such as the exchange of chips in a matter of days rather than weeks as it is the case for traditional cold atom setups. The cryogenic environment will also help to suppress blackbody-induced decay of Rydberg excitations which is an important limitation in current quantum simulation and information processing experiments with Rydberg atoms.
Currently, the Rydberg excitation scheme is set up and the first generation atom chip is being fabricated and tested. When the cryostat arrives, the atom chip will be integrated into the setup, which will allow the interaction of Rydberg atoms and a microwave waveguide resonator on the atom chip.
The chamber design with magnetic transport can be seen in the following from all sides:
The chamber design with the cryostat is planned to look like this (left) and the current experimental setup without the cryostat for now can be seen on the right:
If you are interested in joining the project for a BSc or MSc project, as a PhD researcher or postdoc, please contact Sebastian Hofferberth.