A qubit can be made from two internal energy levels of a charged atom, or ion, depicted here as different atomic orbitals. Metal electrodes, shown here as a gold chip, can trap multiple ions in a chain. Laser beams zap the ions to perform computational operations. In the simplest operation, a laser switches the ion qubit from the lower energy state (sphere) to a higher energy state (four-leaf clover). (Credit: Olena Shmahalo)
Credit: Olena Shmahalo/The Quantum Atlas (CC BY-NC-SA 4.0)