ул. А.Невского, д.14
An international team of scientists, which included IKBFU's Anatoly Snigirev (head of the X-ray optics laboratory) and Piotr Yershov (a Ph.D. student working from the same laboratory, conducted a study of ultrahigh yield strength nanodiamonds. These are 10-20 micrometer balls (1 millimeter would fit a line of 50 to 100 of such balls) able to withstand pressures up to one terapaskal (10 million atmospheres), or almost three times the pressure in the center of the Earth.
The study was carried out by a group of scientists headed by Natalia and Leonid Dubrovinsky (University of Bayreuth, Germany), who had originally come up with the technology of synthesizing such balls. First, one creates balls out of nanocrystalline diamonds, for which the so-called glassy carbon is compressed at a pressure of 177 thousand atmospheres at a temperature of 2000 degrees Celsius. Then those balls that remained transparent, are recompressed at 220 GPa (2.2 million atmospheres).
Says Anatoly Snigirev, head of the X-ray Optics laboratory at the IKBFU:
"We wanted to understand the processes happening with diamond microspheres under such pressure. Your typical optical microscope does not allow to see the a micron size sample in a high-pressure chamber, where even the anvil is made of diamond. We offered our colleagues to use our method of phase-contrast microscopy, which helps you to see the process in the X-ray".
An article about the synthesis of a new ultrahigh yield strength material was published in a prestigious scientific journal, «Science Advances». As reviewers have pointed out, the study has many implications for further work in physics, chemistry, and even geology. Firstly, the results allow a better understanding of the processes occurring inside the Earth now and in the process of its development. Secondly, this study greatly expands the possibilities for the creation of new materials, including high-temperature superconductors. Thirdly, the new material can be used as a basis for presses, capable of developing these ultra-high-pressures: in fact, the pressure of 1 terapaskal is not the limit, it's just that the diamond anvil could not withstand heavier loads. Finally, the new material can be used to create lenses for X-ray scattering devices.
"For many years, we have been working to create lenses for X-ray devices. The pattern is simple: the lighter and denser the material, the better. So we have been trying different materials. For example, a lot of work has been done with beryllium, but it has fine-grained structure, which affects the results of research. There are other disadvantages to using it. A few years ago we started working with diamonds. But these new nanodiamond balls are a completely unique material: they are ultrahigh yield, clear and light. We have already decided, together with our colleagues, that we will continue working on trying to use these balls as lenses. These will be negative lenses, but they will perform stunningly. Some of our experiments will be carried out at our laboratory at the IKBFU.