VSI Seminar: Chunhai Lyu

Speaker:
Chunhai Lyu

Title:
Precision Physics with highly charged ions: atomic clock, dark matter, and spacetime

Abstract:
Trapped ions are among the most pristine quantum systems, offering unparalleled precision for tests of fundamental physics and the development of next-generation optical clocks. In this seminar, I will present our recent theoretical work on highly charged ions (HCIs) – systems that are exceptionally insensitive to external perturbations – and their application in precision metrology. A key focus will be our newly developed periodic table tailored for HCIs. It allows us to systematically uncover more than 700 suitable clock transitions hidden in the fine-structure terms of open-shell ions across over 70 elements. Our calculations project that these transitions can reach fractional frequency uncertainties well below the 10^(-20) level, making them attractive candidates for ultrastable clocks. Beyond timekeeping, we will also show that precision spectroscopy of these transitions can have applications in the extraction of nuclear parameters for elements across the periodic table, the search of new bosons that couple electrons to neutrons, and the test of time-dilation effect of spacetime dynamics.

^References:

^{[1] C. Lyu, Phys. Rev. A (to be accepted)
[2] C. Lyu, C. H. Keitel and Z. Harman, Phys. Rev. Research 7, L042071 (2025)
[3] C. Lyu, C. H. Keitel and Z. Harman, Commun. Phys. 8, 3 (2025)
[4] K. Kromer, C. Lyu, et al., Phys. Rev. Lett. 131, 223002 (2023)
[5] A. Wilzewski, et al., Phys. Rev. Lett. 134, 233002 (2025)
[6] M. Door, et al., Phys. Rev. Lett. 134, 063002 (2025)}