Speaker
Description
Extremely high precision measurement of frequency ratio and difference realized by optical atomic clocks enables us to perform not only accurate time-keeping but also searches for new physics. One of the earliest works on this is the search for time variation of fundamental constants, such as the proton-to-electron mass ratio and the fine structure constant. Recent trend is to precisely measure isotope shifts to investigate new force between an electron and a neutron. Ytterbium is one of the most popular atoms for these purposes. Initially, transitions in Yb+ ions were utilized. Recently, the new clock transition at 431 nm with an f electron excited is expected to serve as an important role in these topics.
In this talk, I first describe a brief overview of the topic. I then discuss my recent work on the 431 nm transition and a search for the new force between an electron and a neutron. Finally, I will describe the future direction of the research including the search for time variation of fundamental constants in my group.