January 07, 2021
The research groups of Li Chuanfeng and Zhou Zongquan of the Guo Guangcan academicians of the University of Science and Technology of China have made important progress in the field of quantum storage, and for the first time realized an on-demand readable integrated solid-state quantum memory. The results were published in "Physics Review Letters" a few days ago, and are of great significance for realizing large-capacity quantum storage and building quantum networks. Quantum memory is the core device for building large-scale quantum networks. Quantum relay or quantum U disk based on quantum memory can effectively overcome channel loss and extend the working distance of quantum network.
The so-called on-demand reading refers to the time required for the photon to be read into the memory after it is written into the memory. It is essential for realizing functions such as synchronous operation in a quantum network. However, the existing integrable solid-state quantum memories in the world are all based on simple atomic frequency comb schemes, and their read-out time is preset before the photon writes and cannot be read on demand. In order to achieve on-demand reading, the research group adopted an improved quantum storage scheme, that is, the electric field modulated atomic frequency comb scheme. By introducing two electric pulses, the Stark effect is used to control the evolution of rare earth ions in real time. The read time of the memory.