Spectral control over γ-ray echo memory
1Physics, National Central University, Taoyuan, Taiwan
* Presenter:WEN-TE LIAO, email:wente.liao@gmail.com
We theoretically study a nuclear frequency comb memory system made of multiple nuclear targets under hyperfine splitting and Doppler shift [1,2]. In frequency domain the single γ-ray absorption line splits into multiple lines with equal spacing and becomes a comb structure. We introduce spectral shaping and dynamical splitting to the frequency comb structure respectively to optimize the use of a medium and to break the theoretical maximum of echo efficiency, i.e., 54%. Spectral shaping scheme reduces the required sample resonant thickness for achieving high echo efficiency of especially a broadband input. Dynamical splitting method significantly advances the echo efficiency up to 67%. Two equivalent nuclear frequency comb memory systems will be presented in this talk.
[1] X. Zhang, WTL, A. Kalachev, R. Shakhmuratov, Marlan Scully, Olga Kocharovskaya, arXiv:1812.11441 (2018)
[2] C.-J. Yeh, P.-H. Lin, X. Zhang, Olga Kocharovskaya, WTL, arXiv:1907.02672 (2019)

Keywords: quantum memory, x-ray, gamma-ray, echo memory