Ultralight axion dark matter search with DANCE*

Axion and axion-like particles are leading candidates for ultralight dark matter, and there have been enormous efforts to search for their signatures through a variety of experiments and astrophysical observations. Axion may cause a polarization rotation of light through the parity-violating interaction with photons. Recently, we have proposed to search for axion dark matter by enhancing the polarization rotation effect using a bow-tie optical ring cavity [PRL 121, 161301 (2018)]. We have shown that this Dark matter Axion search with riNg Cavity Experiment (DANCE) can improve the sensitivity to axion-photon coupling for axion mass m_a<10^{-10} eV by up to several orders of magnitude, compared with the current best limits. Currently, a prototype experiment DANCE Act-1 is underway at Tokyo to demonstrate the feasibility of the method. In this talk, I will present the principle of DANCE and the status of DANCE Act-1, including our first results from May 2021 run [arXiv:2303.035947].