# Optical, Atomic, and Photon Interferometers for precision measurements

- Speaker: Prof. Yoon, Tai Hyun (Korea Univ)
- Date: December 05, 2017
- Place: Science Building 433

In this talk, I will discuss recent develop of Yb optical lattice clock with an accuracy of 10^(-18) that is one of the promising candidate for the new definition of the SI second (s) and the meter (m). For this ultra-precise and stable operation of Yb optical lattice clock, atomic and optical interferometers played major roles. For example, an atomic Ramsey spectroscopy with a Ramsey time of an order of 1 s was demonstrated with magic-wavelength-trapped Yb atoms. For the demonstration of such a Ramsey atom interferometer, a mHz-linewidth coherent laser was constructed with a ultra-stable and low-drift Fabry-Perot reference interferometer. In addition, I will discuss the application of two-slit interferometer in time domain with dual frequency comb spectrometer to detect molecular transitions in a few fs time scale. Finally, a new kind of single photon interferometer will be introduced for the high-resolution quantum spectroscopy with undetected signal photons based on the feature of induced quantum coherence due to indistinguishability of two single-photon-added states of idler photons.