China developed tunable extreme ultraviolet free electron laser (Figure)
China developed tunable extreme ultraviolet free electron laser (Figure) | Inside China
■ newspaper reporter Chen Huanhuan
atomic, molecular detection is the basis of physical and chemical research, but because of the limitations of existing equipment, the majority of molecules and free radicals is difficult to linen-photon ionization, unable to penetrate a lot of research to become scientists problem.
The
aimed at addressing the problem of the experimental device will be built in China. March 12, with a total budget of $ 1.4 billion of major national research equipment special “is based on a comprehensive experimental study of tunable extreme ultraviolet coherent light source device” was officially launched in Dalian. It will become a free electron laser only a work in 50 to 150 nm range and tunable coherent and high brightness.
total project person in charge, Xue-Ming Yang, Chinese Academy of Sciences, said the development of the device will greatly enhance the level of China’s experiment in energy and other basic sciences, and hope to become an important research base related fields.
combination
responsible for one of
project, the Chinese Academy of Sciences the DICP researcher Dai Dongxu said energy study of coal pyrolysis and other intermediate products of the combustion process often exists in the form of atoms, molecules, radicals, these microscopic particles are ionizing ions into electrical signals to be tested. Therefore, high sensitivity, high temporal resolution and species-resolved detection and study of microscopic particles is essential.
However, most of the molecules or free radicals, stimulate the ionization wavelength in the extreme ultraviolet (50 to 150 nm), traditional laser wavelength is generally in the near ultraviolet to near infrared wavelengths (300 to 1000 nm). This has resulted in traditional laser ionization of microscopic particles absorb more photons, the efficiency and sensitivity was the geometric order of magnitude lower, and easy to break the product.
To resolve this problem, the scientists have proposed the use of free-electron laser technology to produce extreme ultraviolet coherent light. The technology is considered to be the most effective way to detect microscopic particles. The free-electron laser wavelength can cover from the hard X-rays to the far-infrared band, especially the use of high gain harmonic generation free electron laser (HGHG) technologies used to produce ultra-high peak brightness, the ultrafast temporal characteristics and good coherence great application value.
but the technology until about ten years before the experiment be verified. Among them, the Chinese Academy of Applied Physics, where a few years ago the construction of China’s first free-electron laser, and successfully carried out related experiments.
in Dalian, a scientific research for many years trapped in the particle detection problem the scientists sit still. He is to experiment with their own R & D instruments and famous Xue-Ming Yang. Xue-Ming Yang find Shanghai Applied Physics, hope that both sides can work together to develop new equipment.
the
Shanghai is also aware of the accumulated experience, grasp the free-electron laser wavelength from 200 nm down to less than 150 nm, and wavelength tunable. The two hit it off in 2011 after several years of argument, a joint application by the National Natural Science Foundation of major national research equipment special.
January 20, 2009, Shanghai Applied Physics announced: the researcher Zhao Zhentang led the free-electron laser research team in the international community take the lead in achieving a the HGHG free-electron laser wavelength of a wide range of continuously adjustable.
“In this project, the DICP and Shanghai should matter is the perfect combination.” Daidong Xu said that the completion of the Shanghai Synchrotron Radiation things have a large science and engineering construction and management experience in Shanghai and have a great deal key technologies.
“dare” to “daring”
Dai Dongxu introduced, free-electron laser in the 21st century began to prosper together. Currently, several research and development of free-electron laser units have their own strengths, some leading indicators of the wavelength is more, technology is very difficult, but no one can achieve wavelength tuning.
at Hefei National Synchrotron Radiation Laboratory is able to provide the vacuum ultraviolet the best experimental conditions, Xue-Ming Yang group has assisted in the past to make a good experimental results. Synchrotron radiation light source, after all, is not a laser, the remaining differences in the coherence, the peak power and time characteristics.
to address these issues, the DICP starting from the actual needs of the request, of Applied Physics, where the design will be targeted to solve practical problems in the experiment.
It is reported that the equipment of the project will be largely independent research and development. “This technology abroad in its development phase, some special indicators can only be made from abroad to buy the equipment from scratch developed,” said Dai Dongxu.
The total project budget of 140 million yuan, the National Natural Science Foundation funded 103 million yuan for the development of the free-electron laser and the experimental setup, the Chinese Academy of Sciences the DICP raised about 0.4 billion for infrastructure and public facilities. The scientific objectives of the project is the development of a HGHG mode wavelength tunable extreme ultraviolet coherent light source and the use of the experimental setup of the light source of this superior performance. This will also be unique in the world of basic science experiment platform.
It is reported that the current funding already in place, the device plan to be completed before the end of 2015. Equipment sharing, and the country can be applied to the physical, chemical, biological, energy and other fields. Daidong Xu said: “After completion of installation, previously undetectable will be able to measure to the bad signal will become clear, do not experiment also dare to do.”