Photon retention in coherently excited nitrogen ions Academic Article uri icon


  • Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation. Alkali metal vapors, despite the numerous shortcomings, are traditionally used in quantum optics as a working medium due to convenient near-infrared excitation, strong dipole transitions and long-lived coherence. Here, we proposed and experimentally demonstrated photon retention and subsequent re-emittance with the quantum coherence in a system of coherently excited molecular nitrogen ions (N2+) which are produced using a strong 800 nm femtosecond laser pulse. Such photon retention, facilitated by quantum coherence, keeps releasing directly-unmeasurable coherent photons for tens of picoseconds, but is able to be read-out by a time-delayed femtosecond pulse centered at 1580 nm via two-photon resonant absorption, resulting in a strong radiation at 329.3 nm. We reveal a pivotal role of the excited-state population to transmit such extremely weak re-emitted photons in this system. This new finding unveils the nature of the coherent quantum control in N2+ for the potential platform for optical information storage in the remote atmosphere, and facilitates further exploration of fundamental interactions in the quantum optical platform with strong-field ionized molecules.

published proceedings


altmetric score

  • 7

author list (cited authors)

  • Yao, J., Wang, L., Chen, J., Wan, Y., Zhang, Z., Zhang, F., ... Cheng, Y. a.

citation count

  • 4

complete list of authors

  • Yao, Jinping||Wang, Luojia||Chen, Jinming||Wan, Yuexin||Zhang, Zhihao||Zhang, Fangbo||Qiao, Lingling||Yu, Shupeng||Fu, Botao||Zhao, Zengxiu||Wu, Chengyin||Yakovlev, Vladislav V||Yuan, Luqi||Chen, Xianfeng||Cheng, Ya

publication date

  • August 2021