Ryd-Yb tweezer array

We recently started a new atom array experiment with neutral Yb atoms!

We have open PhD and PostDoc positions!!

Quantum computing and quantum simulation with fermionic ¹⁷¹Yb

Neutral-atom arrays have gained increasing importance in the development of quantum computing architectures. More recently, high-fidelity single- and two-qubit operations have also been demonstrated with
alkaline-earth(-like) atoms AELA, which offer unique opportunities for high-fidelity detection via shelving, trapping of Rydberg states and high-fidelity single-photon Rydberg excitations. As part of the Munich Quantum Valley (MQV) we are currently building a new tweezer-array platform, where single fermionic ¹⁷¹Yb atoms are trapped in optical tweezers and interactions are induced via highly-excited Rydberg states.

We are currently looking for a Postdoc and a PhD student!!

Qubit encodings in ¹⁷¹Yb - the “omg” architecture

Neutral Yb atoms have two valence electrons, hence the level structure is decomposed of singlet and triplet states. The absolute ground state ¹S₀ is labeled as |g> and the excited clock state ³P₀ as |m>. The optical transition connecting the two clock states is weakly allowed for the fermionic isotopes with an ultranarrow linewidth, which is used for optical lattice clock forming the optical qubit |o>. The unique feature of the fermionic isotope ¹⁷¹Yb is that is has a nuclear spin I=1/2, which supports multiple qubit encodings.

Our atom array of individual ¹⁷¹Yb atoms

In order to achieve high-fidelity control on the optical clock transition, we work with tweezer traps at the clock-magic wavelength of 759nm, where the differential light shifts for that transition vanishes.

Above you see an averaged image of individual ¹⁷¹Yb atoms confined in a 2D array of 64 optical tweezers, generated using crossed acousto-optic deflectors (AODs). The atoms are loaded from a magneto-optical trap operating on the ¹S₀→³P₁ transition, with enhanced loading fidelities of about 80%.

We group the atoms into pairs to study Rydberg-mediated interactions between neighboring sites. When driving the excitation to a Rydberg state, we observe the first signatures of pair interactions. For neighboring pairs, the Rabi coupling is enhanced by a factor of √2, reflecting the strong interactions between atoms in the excited Rydberg level. The resulting signal exhibits a characteristic beating pattern arising from singly and doubly occupied neighboring tweezers.