Trapped-ion qubits encode quantum information in long-lived internal states — typically hyperfine or optical transitions — of individual atomic ions held in place by electromagnetic fields and manipulated with laser or microwave pulses. Because every ion in a small trap can be coupled to every other through their shared motional modes, the platform offers connectivity between qubits that many solid-state platforms have to engineer explicitly.

Beyond digital gate-based computation, a trapped-ion system’s motional modes can themselves be used as an analog simulator: by engineering how those modes couple to their environment, researchers can reproduce the dynamics of another quantum system — including, more recently, systems held at a deliberately chosen finite temperature rather than as close to absolute zero as the hardware allows.