Екатерина Вавилова – All sciences. №7, 2022. International Scientific Journal (страница 3)

At the time of 1982, he, being at the very dawn of his strength, at the age of 41, saw the next fruits of his labors – the higher attestation commission awarded the academic title of professor to Also Mirzamakhmudovich. From 1984 to 1987, Tozhiboy Mirzamakhmudovich took the honorary post of vice-rector of the evening correspondence department of the Fergana Polytechnic Institute, actively continuing his scientific activities, but the craving for knowledge, the thirst for creation continued to torment him, which is why from 1987 to 1991 he assumed the post of vice-rector for Research, where he was able to plunge again into the amazing world of science and creation.

Mirzamakhmudov was widely known and recognized for his work in the field of research of photoresistive and photoelectric phenomena in semiconductor film elements. To put it more simply, these film elements transmitted energy when illuminated, but in its absence they did not immediately lose it, but reduced the amount of transmitted current very evenly, up to a certain amount, which they stored like a memory element!

In this field, Mirzamakhmudov and a group of his students conducted a series of studies on the development and study of photo-portrait elements, those very memory cells that arise due to the internal field of p-n transitions. For the first time in the world, photoelectric elements from triple semiconductor compounds were discovered, that is, if single or binary compounds were previously used and their properties were already studied, then triple compounds were discovered here for the first time, surprisingly their properties were much more complex than binary, not to mention single cases. And in 1988, under the leadership of Mirzamakhmudov, a new effect was first revealed – an abnormally high photoelectromagnetic voltage without an external field in two film semiconductor materials, which meant that not only when an electric current passed through the crystals, but also through the film, the Hall effect was observed – a deviation of electron flows in a magnetic field, along with the fact that the current flowed and straight, deviating a little, so even in the film it was possible to separate the charge.

During his long scientific career, which lasted more than 50 years, Mirzamakhmudov published more than 100 scientific papers, two monographs received more than 10 author’s certificates. He is the author of several methodological manuals and the editor of textbooks on theoretical physics. Some of his works have been published in Bulgaria, Czechoslovakia and Japan. At the initiative of Tozhiboy Mirzamakhmudovich, many scientific laboratories studying the most pressing issues and problems of modern science of that time were opened at the Fergana Polytechnic Institute, a postgraduate school and small commercial enterprises were established, and a research laboratory for the study of the physicochemical properties of semiconductor solar cells was established under his direct supervision.

Tozhiboy Mirzamakhmudovich devoted a lot of effort and energy to establishing scientific contacts with leading centers and universities of the country. Mirzamakhmudov had the ability to see a future scientist in a student and a young specialist, to direct his activities in the direction of scientific research. More than twenty PhD theses have been defended under his leadership.

The results of the research of the Institute’s employees who worked under the leadership of Mirzamakhmudov are widely implemented today in the field of physics, mathematics, chemistry and other sciences. And many of his scientific works continue to be published posthumously, honoring his memory, a vivid example of this is the textbook “Electronics Asoslari” published in 2022, co-authored by his student B. Karimov.

The great scientist continued his work, leaving behind a great legacy not only in the face of his numerous works, but also not small students who are now candidates, doctors of sciences, professors, and some have already gone with their teacher to another world.

Tozhiboy Mirzamakhmudovich himself left our world on November 9, 2009, leaving behind the great memory of the great scientist…

PHYSICAL SCIENCES

THE USE OF NEW NANOSTRUCTURE METHODS ALLOWING TO INCREASE THE MONOCHROMATICITY OF THE BEAM DURING ACCELERATION

UDC 621

Rinat Fuadovich Rumi

Senior Researcher, Head of the Laboratory of Accelerator Technology at the Research Institute “Physics of Semiconductors and Microelectronics” at the National University of Uzbekistan

Laboratory of Accelerator Technology at the Research Institute “Physics of Semiconductors and Microelectronics” at the National University of Uzbekistan, Tashkent, Uzbekistan

Abstact. The development of accelerator technology has been actively observed after numerous works by Ernest Rutherford, from the discovery of the planetary model and the implementation of the first nuclear reaction to the present day. And it is worth noting that for each time there were quite interesting requirements for charged particle beams, among which the most popular requirement at almost all times was the beam energy, then its current can be noted, but one of the most important among them is the monochromaticity of the charged particle beam.

Keywords: monochromaticity, monoenergetics, charged particle beam, accelerator, nanostructures.

Аннотация. Развитие ускорительной техники наблюдалось активно после многочисленных работ Эрнеста Резерфорда, от открытия планетарной модели и осуществления первой ядерной реакции до сегодняшний дней. И стоит отметить, что для каждого времени существовали довольно интересные требования к пучкам заряженных частиц, среди коих самым популярным требованием почти во все времена являлась энергия пучка, затем можно отметить его ток, но одним из важных среди них является монохромотичность пучка заряженных частиц.

Ключевые слова: монохроматичность, моноэнергетичность, пучок заряженных частиц, ускоритель, наноструктуры.

Introduction

Initially, it is necessary to give a general concept of the monochromaticity parameter itself, which is often associated with monoenergetics. The whole point is that the beam, after its formation by thermionic, auto- or other emission, has a heterogeneity in energy, which is why the particles in its various regions have different, albeit slightly distinguishable energies. With acceleration, their given spread or gradient increases, although it becomes smoother. For example, on accelerators of the 80s, an example of which is the SOKOL-2 accelerator, monoenergetics of up to 5 keV is achieved at 2 MeV of the total beam energy, while on modern accelerators, at an energy of 20 MeV, an accuracy of up to 1 keV is achieved in maximum accuracy.

Problems

If the question arises about the figure of this value, then it is thanks to it that we can talk about the effectiveness of the entire reaction, because as far as the energies in the beam are homogeneous and have a value close to each other, so much more of them will be close to the energy desired for this reaction channel – to the necessary resonance, which will make the reaction more efficient.

Today, exo-energetic nuclear reactions are known, the output particles in which have more energy than at the input, but at the same time such a reaction takes place only for a part of the particles due to the very smallness of the total monoenergetics of the beam.

Solving the problem

To achieve results, that is, to increase the efficiency of the conducted nuclear reaction, it is necessary to increase monoenergetics, and for this it is necessary to develop a method for equalizing energy on different parts of the beam. As is known, in a magnetic field, under the influence of the Lorentz force (1—2), particles are deflected, while the beam at the maximum energy in its center and decreasing closer to the edges is stratified, passing into a kind of energy gradient.

Further, it is more likely that the beam will be divided into component parts, where the losses will be much less than it would be with “beam selection” with losses of more than 90%, namely, for divisions, the losses will be only 12%. Nanotubes, in themselves, are formations resembling carbon tubes that transmit a charge, but at the same time separated from each other by a dielectric layer of molecules.

For the formation of a charge in such a system, a vertical and horizontal transmission line is carried out to each tube, with the closure of which this particular cell is charged. When a second system of the same type is located opposite, a potential difference arises between them, thanks to which it is possible to give energy in the gradient spectrum, the reverse of the incoming beam gradient, while losing only 12% of the total number of charges, and, accordingly, current.

At the same time, it is important to note that although it is not so difficult to vary the potential differences within the framework of a modern 1 keV accelerator, but the accuracy is not infinite. While maintaining the same voltage ratio for 20 MeV, an accuracy of up to 0.04—0.05 eV can be achieved, which is a shocking result.