Ultra-fast X-ray breakthrough

Electromagnetic induced transparency or EIT has been known for quite a long time. This phenomenon is used to control properties such as dispersion and absorption in gases, allowing gas to become transparent at a certain wavelength under the action of a laser. However, until now, EIT has not been used in x-rays.

Researchers at Argonne National Laboratory in Illinois are changing that. Their study predicts the use of EIT for x-rays in neon gas under the effect of a laser called 'Transparency caused by electromagnetism for x-rays' and published in Physical Review Letters .

One of the researchers, Christian Buth, said: 'The object of study is very fast x-ray pulses. With ultra-fast x-rays, we can photograph atoms in molecular motion, almost like a movie. '

(Photo: imit.kth.se) Linda Young, a researcher with the group, pointed out that one of the interesting applications from this study is that it is possible to observe the structure of a complex molecule. ' We can watch molecules react in real time and understand basic interactions .'

One of the reasons that this method of capturing these ultra-fast x-ray pulses is interesting is the relatively low cost.'There are expensive x-ray sources available,' said the team's third member, Robin Santra, 'and we have just discovered that a laser can produce short x-ray pulses. practical.' Buth added: "This method is cheaper and shorter pulses are important, because pulses longer than molecules only vibrate and the image will be blurry and unclear."

" This method can be applied in pump-prope testing, allowing scientists to better understand real changes, " explains Santra . He explains: 'In all pump prope tests, you exert a clearly defined force on the molecule, causing it to be disturbed in a controlled manner. Then, you wait for the most time. will see that the molecule has a clear change in shape. '

Scientists are now studying the evolution of time for light absorption and observing it in an indirect way, said Santra.And super-fast x-rays allow direct observation. 'With these ultra-fast x-rays, we impact the molecule with an initial pulse, and then probe it with another pulse. Each pulse is clearly defined, in terms of execution time and relative time delay. You can also manipulate more pulses and directly observe the molecular evolution with these pulses according to the real-time system. '

In this case, Argonne researchers suggest using EIT in neon to produce extremely short x-ray pulses. Linda Young explained: 'We tried it with krypton, but it has a high nuclear charge and no big impact. In contrast, Neon has a lower charge, and the inner shell disintegration takes longer, which makes it more pronounced. Our theory is, by impacting an 800 nanometer laser, we can make the normally opaque neon gas become transparent. ' Ms. Young also pointed out that transparent properties are reversible, 'only when this gas laser is transparent.'

EIT for X-rays is still at the theoretical stage. However, Ms. Young is planning to conduct a trial at Lawrence Berkeley National Laboratory with Argonne Atomic Physics Group. This test will demonstrate whether the prediction of neon transparency is experimental.

Thanh Van