In January 2024 two nice research results were published:
1. First circular Rydberg Qubit of an alkaline-earth atom
In the CiRQus project, we have demonstrated the first trapped circular Rydberg atoms of Strontium. Coherence time and gate fidelities in Rydberg atom quantum simulators and computers are fundamentally limited by the Rydberg state lifetime. Circular Rydberg states are highly promising candidates to overcome this limitation by orders of magnitude, as they can be effectively protected from decay due to their maximum angular momentum. Alkaline-earth metal atoms are particularly promising in this context, as they feature an additional optically active electron, which provides a completely new toolbox for manipulation and detection.
2. New fine-structure qubit
In our recent experiments, we have realized a novel neutral atom qubit encoded in two metastable fine-structure states of single Strontium atoms trapped in an optical tweezer. This qubit is at the core of the QRydDemo project, where we are setting up a 500 qubit neutral atom quantum processor. One of its unique properties is the possibility to speed up single-qubit gate operations by orders of magnitude, to timescales on par with the fast Rydberg-mediated two-body gates.
