RQC Seminar

17th RQC Seminar

• Speaker

  Dr. Po-Chen Kuo
  (Department of Physics and Center for Quantum Frontiers of Research and Technology (QFort), National Cheng Kung University）

• Date

  16:00-17:00 (JST), November 4, 2022 (Friday)

• Venue

  Hybrid (Zoom / Wako Welfare and Conf. 2F Large Meeting Room RIKEN Wako branch)

• Title

  When Kondo effect meets ultrastrong coupling of cavity photons

• Inquiries

  rqc_info[at]ml.riken.jp

Abstract
The Kondo effect has triggered intense interest for the investigation of strongly quantum many-body correlations. Recently, ultrastrong coupling between light and matter has attracted great attention for its various applications. However, the investigation of the Kondo effect with ultrastrong light-matter coupling is still lacking because of the high computational cost. Here, we make an essential step to study this problem by using the hierarchical equations of motion approach to obtain the system's dynamics and electronic density of states, which are strongly influenced both by electronic baths and the bosonic fields. We show that the results from the hierarchical equations of motion approach are consistent with the master equation when the couplings of electronic baths are out of the Kondo regime. We find that the ultrastrong coupling of the cavity fields can noticeably suppresses the electronic Kondo resonance due to the destruction of many-body correlations of the Kondo cloud. By calculating the entanglement entropy, one finds that the reduction of many-body correlations comes from the formation of the electron-photon dressed states. Our findings pave the way for the control of the Kondo effect by using the ultrastrong couplings of photons.