To the 80th Anniversary of MEPhI: a New Tokamak Is Being Made at the University

The 80th anniversary of the university is a good occasion to talk about its long-term plans. One of the most interesting events planned at the Institute for Laser and Plasma Technologies (LaPlas) of the MEPhI for the coming years is the development and creation of a new MEPHIST-1 tokamak, technically more advanced than the MEPHIST-0 facility already available at the university. The work was supported by the Priority 2030 program.

Modernization of tokamak "MEPHIST-0"

Tokamak (toroidal chamber with magnetic coils) is an installation for confining plasma in a magnetic field in order to achieve the conditions necessary for controlled thermonuclear fusion to occur. Back in 2019, the MEPHIST-0 training and demonstration tokamak was created at MEPhI, and at the initial stage, its creation was financed not only by the university, but also by private donations from graduates of the Plasma Physics Department. Then the development of the tokamak was actively supported by the State Corporation Rosatom.

"MEPHIST-0" is intended primarily for practical work with students, but it is also used in scientific research, moreover, the installation is constantly being upgraded. So, over the past years the electromagnetic system of "MEPHIST-0" was completely replaced - this made it possible to create a higher, more uniform and more stable magnetic field. The preionization system (creation of primary plasma) was equipped with a power measurement unit, which makes it possible to optimize the power of the installation.

A system of laser plasma interferometry, developed by the staff of the Department of Laser Physics, was tested on the tokamak; now a similar system is being developed for the T-15MD tokamak. Work is underway to implement high-frequency plasma heating. The process of creation and modernization of "MEPHIST-0" allowed both the students participating in this and the university staff to study, said Stepan Krat, senior researcher at the laboratory "Physical and chemical processes in the walls of thermonuclear installations".

But today on the agenda is the development of a new installation "MEPHIST-1". The steel discharge chamber of the tokamak has already been manufactured at the Experimental Plant of Scientific Instrumentation of the Russian Academy of Sciences, but the appearance of a new installation “in metal” will not occur before 2025. In the next 1.5 years, it is planned to continue the development of the device of the future device "on paper". As Stepan Krat said, in the process of creating "MEPHIST-0" they had to learn from their own mistakes, and when creating a new tokamak, all the experience gained by the team will be taken into account.

"MEPHIST-1" will differ from its predecessor by a large number of technical changes, in particular, the possibility of using high-temperature superconductors to create an electromagnetic field is being considered. It is possible that "MEPHIST-1" will become the first tokamak in Russia with high-temperature superconductors. It is also planned that the new tokamak will be much more powerful than the old one. The developers of the installation hope that they will be able to achieve a magnetic field with a strength of up to 2 Tesla, while in "MEPHIST-0" this figure does not exceed 0.8 Tesla. In addition, if "MEPHIST-0" has six ports for connecting equipment, then "MEPHIST-1" will have 36 of them.

When "MEPHIST-1" appears, its predecessor will have purely educational functions, it will be used primarily for laboratory work of undergraduate students. Well, the new MEPhI tokamak will be used for research by undergraduates and graduate students, work at the facility will allow them to write master's and candidate's dissertations.