Recently, the State Key Laboratory of High-Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, in collaboration with Shanghai Jiao Tong University and other institutions, realized the "photon retention" effect in coherent excited nitrogen ions, and verified the possibility of coherent manipulation of photons in atmospheric ionic gas.The findings are in the journal Science Bulletin.
Nitrogen is the most abundant gas in air.A series of recent scientific studies have found that nitrogen ions produced by strong field ionization are a potential new platform for studying quantum coherence effects.Compared with the traditional laboratory gases such as alkali metal vapor, Rydberg quantum gas and ultra-cold atom, nitrogen ion is considered as a novel quantum optical platform for studying the interaction between light and matter and the coherent manipulation of photons due to its rich energy level structure, relative stability and safety in chemistry.At the same time, due to the rich content of nitrogen molecules in the air, the quantum optics research platform is expected to move from the laboratory to the outdoor atmospheric environment, so as to achieve coherent manipulation of photons in the atmosphere.
For these reasons, THE Shanghai Institute of Optics and Mechanics, in collaboration with Shanghai Jiao Tong University and other institutions, verified the photon retention effect in coherently excited nitrogen ion gas.It is found that after nitrogen is ionized into nitrogen molecular ions by femtosecond laser field, the resulting quantum coherence properties retain photons in the ionic gas.These photon information could not be directly detected in previous studies.In this study, we propose an effective method to read the remaining photons. The coherent ultraviolet radiation can be directly observed by the detector through the interaction of the second mid-infrared laser pulse injected with the delay and the remaining photons. Thus, the coherent photon retention effect in nitrogen ions is verified.Verification of photon retention effect in nitrogen, an atmospheric gas, not only confirms that nitrogen ion is an excellent platform for quantum optics research, but also points out the possibility of realizing optical information processing and coherent optical information storage at room temperature through abundant nitrogen in the outdoor atmosphere in the future.
The basic principle of "photon retention" effect in coherently excited nitrogen ions
Related work has been supported by the National Natural Science Foundation of China, National Key RESEARCH and Development Program, Shanghai Municipal Science and Technology Major Special Project, Shanghai Excellent Academic Leader, Shanghai Natural Science Foundation, Cas Strategic Priority Science and Technology Special Project, CAS Youth Promotion Association and other projects.