High precision and scalable multi-focal beam steering system for digital fermionic quantum computing

Digital fermionic quantum computing allows versatile and universal programmability by enabling the simulation of problems beyond the currently existing NISQ (noisy intermediate-scale quantum)-era quantum computers. This work deals with a fundamental requirement, which is scaling the number of simultaneously controllable and detectable qubits, by addressing a 2D lattice of Li atoms using multiple focused laser beams. The wave-optical limitations and possible optical design configurations are investigated for addressing the atomic grid of 20 x 10 Li atoms by at least 5 laser foci having minimum crosstalk between neighboring lattice sites, with the consideration of scalability. The focused laser beams, hence, should be laterally steered over the lattice area with extremely high positional accuracy and high speed for all-to-all connectivity. The polarization state of the focused beams should be maintained to improve the efficiency of the consequent atomic Raman processes. A scalable optical and mechanical design is proposed, to satisfy the optical and physical requirements, with the consideration of technological challenges and solution ways.