November 14, 2024

Scientists Realize Noiseless Photon-Echo Protocol – Key to Long-Distance Quantum Communication

In this research study, the scientists executed NLPE procedure in Eu3+: Y2SiO5 crystal to function as an optical quantum memory and used a four-level aromic system to reduce the noise.
By double rephasing the pulse in the four-level atomic system, they manipulated the spontaneous noise emission to have a various frequency from the signal. It is much simpler to separate the signal from the noise emission.
The results of the experiments revealed that the noise was 0.0015 photons, 670 times less than previous outcomes. Besides, the efficiency of NLPE was more than three times bigger than that of previous procedures.
Moreover, its high performance, high fidelity, and easy-to-achieve entitle NLPE with stunning advantages as a soundless quantum memory procedure.
All of these benefits bring one closer step to long-distance quantum interaction.
Recommendation: “Elimination of noise in optically rephased photon echoes” by You-Zhi Ma, Ming Jin, Duo-Lun Chen, Zong-Quan Zhou, Chuan-Feng Li and Guang-Can Guo, 19 July 2021, Nature Communications.DOI: 10.1038/ s41467-021-24679-4.

The research of entire originality reduced the noise by 670 times compared with previous methods and attained solid quantum memory with high fidelity. By double rephasing the pulse in the four-level atomic system, they manipulated the spontaneous sound emission to have a different frequency from the signal. It is much easier to separate the signal from the noise emission.

Prof. Chuanfeng Li and Prof. Zongquan Zhou from University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) innovatively raised and realized soundless photon echo (NLPE) procedure. The research study of whole originality lowered the noise by 670 times compared to previous techniques and achieved solid quantum memory with high fidelity. The outcomes were released in Nature Communications.
Observed by Erwin Hahn in 1950, photon echo is a fundamental physical interaction in between light and matter as well as an important tool for the manipulation of electromagnetic fields. Nevertheless, the intense spontaneous sound emission generated has the exact same frequency as the signal, it is impossible to separate them in principle.Previous protocols, such as atomic frequency comb and the revival of silenced echo, failed to get rid of the spontaneous sound emission as much as required.