Barium isotope 137 has nuclear spin 3/2, which gives rise to hyperfine interaction and ground state splitting of about 8 GHz. Hyperfine states with there effectively infinite lifetime and long coherence are excellent candidates for quantum information storage and processing. We are working on developing a robust scheme for ¹³⁷Ba⁺ qubit detection.

While it is convenient to store quantum information in hyperfine states of trapped ions, sending this information over any distance longer than a millimeter is best done by using photons. We are studying coherent coupling between quantum states of the trapped ions and single photons.

Short, high-intensity laser pulses can be used to drive fast quantum logic gates between trapped ions. A high degree of control over the pulses properties is necessary for high-fidelity gates.