Progress towards large-scale parallel quantum information processing with trapped Be+ ions

Trapped atomic ions can be entangled with the Molmer-Sorensen gate scheme, a prevalent approach for quantum computing and quantum simulations. Despite high-precision qubit manipulations with small systems, the current limits for scaling up system sizes come from technical and control challenges: digital systems need extensive individual control; the analog limit suffers from the slow gate speeds; both suffer from collisional losses of ion chains due to residual background gas collisions, which can be solved brute-force by cryogenic ion traps at the cost of introducing significant system complexities and vibration-induced decoherence. We present progress towards parallel gates with long ion strings using combined theoretical, numerical, and experimental approaches. We propose fast gates in the non-adiabatic region using laser frequency modulations with spin-phonon error mitigation and robustness against motional heating. We perform extensive numerical searches and compare with experiments to solve the collisional many-body loss mechanism. Finally, we improve the vacuum level by up to an order of magnitude compared to state-of-the-art setups, without the added complexity of cryogenics. Integrating these advantages, the light mass of Be+ should enable fast parallel quantum gates with a hundred qubits and beyond.