Glossary / Quantum computing
Neutral atom
An approach that uses uncharged atoms as qubits, each one held and positioned by laser light.
Tightly focused laser beams, called optical tweezers, trap atoms such as rubidium one at a time in a vacuum and arrange them in a grid. When atoms are raised to a high-energy state, neighbours influence each other strongly, and that interaction is used to perform operations between two qubits.
The strength of the approach is that atoms can be moved during a computation, so distant qubits can be brought together. In late 2023 a team led from Harvard reported running up to 48 logical qubits using 280 atoms[1]. Operations are comparatively slow, and atoms lost during a computation have to be dealt with.
Related terms
- Trapped ionUsing atomic ions, suspended in a vacuum by electric fields and manipulated with lasers, as qubits. Used by Quantinuum and others.
- Superconducting qubitA qubit made from a superconducting circuit, which has zero electrical resistance at very low temperature. Used by IBM, Google, Fujitsu and others.
- Logical qubitA single, robust qubit made by bundling many physical qubits together and running error correction on them.