Researchers from the Quantum Metrology Laboratory at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland, have made a significant advancement in the field of atomic clocks and quantum computing. The team, led by Dr. Jialiang Yu and including Anand Prakash, Clara Zyskind, Ikbal A. Biswas, Rattakorn Kaewuam, Piyaphat Phoonthong, and Tanja E. Mehlstäubler, has published their findings in the journal Nature Communications.
The researchers focused on the highly forbidden electric octupole transition in the isotope Ytterbium-173 (173Yb+), which has a nuclear spin of 5/2. They observed that the nuclear spin induces a quenching effect on the transition, significantly reducing its lifetime. Specifically, the lifetime of the hyperfine state F_e = 4 was found to be ten times shorter than the unperturbed clock state in Ytterbium-171 (171Yb+). This reduction in lifetime has practical implications for the energy industry, particularly in the development of more accurate and stable atomic clocks, which are crucial for synchronizing power grids and managing energy distribution.
The shorter lifetime of the transition lowers the required optical power for coherent excitation, which in turn reduces the AC Stark shift caused by the clock laser. The AC Stark shift is a phenomenon where the energy levels of an atom are shifted due to the interaction with an external electric field, which can introduce errors in atomic clocks. By using a three-ion Coulomb crystal, the researchers demonstrated an approximately 20-fold suppression of the AC Stark shift. This improvement is critical for the scalability of future multi-ion Yb+ clocks, which could be used in various energy applications, such as improving the precision of time-stamped data in smart grids and enhancing the accuracy of energy trading and billing systems.
In addition to the quenching effect, the researchers also reported the unquenched reference transition frequency between the states |^2S_{1/2}, F_g=3⟩ and |^2F_{7/2}, F_e=6⟩ as 642.11917656354(43) THz. They also measured the hyperfine splitting and calculated the quadratic Zeeman sensitivities of the ^2F_{7/2} clock state. These findings contribute to the broader understanding of atomic transitions and their applications in precision metrology and quantum computing.
The research conducted by the NIST team paves the way for the development of multi-ion optical clocks and quantum computers based on 173Yb+. These advancements could have significant implications for the energy industry, particularly in improving the accuracy and reliability of timekeeping systems used in power grids and other energy infrastructure. The practical applications of this research highlight the ongoing efforts to enhance the precision and stability of atomic clocks, which are essential for the efficient and reliable operation of modern energy systems.
This article is based on research available at arXiv.