Individual addressing of trapped ¹⁷¹Yb⁺ ion qubits using a microelectromechanical systems-based beam steering system

The ability to individually manipulate the increasing number of qubits is one of the many challenges towards scalable quantum information processing with trapped ions. Using micro-mirrors fabricated with micro-electromechanical systems technology, we focus laser beams on individual ions in a linear chain and steer the focal point in two dimensions. We demonstrate sequential single qubit gates on multiple ¹⁷¹Yb⁺ qubits and characterize the gate performance using quantum state tomography. Our system features negligible crosstalk to neighboring ions (<3 × 10^-4), and switching speed comparable to typical single qubit gate times (<2 μs).