School of Physics CM/AMO/Quantum Seminar - Dr. Chuankun Zhang

The size and complexity scaling of quantum systems from individual trapped ions to tens of thousands of atoms in optical lattices has driven major advances in precision measurement and quantum technology. Leveraging the exceptional environmental insensitivity of nuclear transitions, we demonstrate a solid-state clock with more than 1015 thorium-229 nuclei hosted in a 1 mm3 crystal, unlocking access to quantum devices with unprecedented large numbers of coherently controlled quantum emitters.

A major technological obstacle in realizing nuclear clocks is the lack of coherent laser light sources at nuclear transition wavelengths. Using a frequency comb laser in the vacuum-ultraviolet (VUV), we resolve the individual nuclear quantum states of the low-energy thorium-229 nuclear transition in a CaF2 crystal host and precisely determine their frequencies, referenced to the JILA strontium-87 optical lattice clock. We systematically characterize the state-dependent clock frequency reproducibility with respect to temperature, doping concentration and time.

This nuclear clock promises a scalable and portable platform for quantum science and metrology. Nuclear-atomic clock comparisons will also enable stringent tests for new physics beyond the Standard Model.