Plasma, known as the 4th state of matter, was first discovered by Irving Langmuir in 1928. We know that more than 99% of the visible matters in the universe is in the form of plasma. The Sun, the largest plasma, the polar lights in the Arctic and Antarctic, lightning and thunders in the ionosphere are a few forms of plasma. Plasma, which is also used in many industries today, also allows the products to be more robust and sterile. We talked about plasma technology with Prof. Dr. Necdet Aslan from Yeditepe University, who established a brand-new plasma laboratory at TUBITAK UME.
What is plasma technology?
As you know, there are 3 states of matter: Solid, liquid and gas. Plasma is called the “4th state”. Plasma is actually a gas, but in some cases it can behave like a liquid. The gases around us are usually one-, two-, three- or four-atoms. For instance, in carbon dioxide there is 1 carbon and 2 oxygen. Gases like this are found everywhere in the atmosphere and are in a neutral state. For example, the carbon in carbon dioxide has a carbon nucleus and electrons around it. The + charge of the nucleus depends on the number of protons and the - charge depends on the number of electrons outside the nucleus. If the number of these is equal, the atom is in a neutral state. If the atom is energized, for example, by heating or applying an external electric or magnetic field, the electrons travel to orbits farther from the nucleus, and some even break off from the atom. This is “ionization”. In this case, the atom becomes + charged as much as the decreasing – charge. Extra electrons can also be attached to the outer orbitals of some atoms, making the atom - charged. There are positively and negatively charged ions and neutral atoms and gases in the atmosphere, and people breathe these every day. Now, let's imagine a glass or stainless steel boiler with most of its internal air evacuated by a vacuum pump. And let’s assume that we put two plates in this and apply a voltage of 500 volts. In this case, there will be an energy transfer to the transferring atoms in the electric field. After the atoms receive the energy, the electrons rotating around the nucleus tend to rise towards the outer layers and break off from the atom. Even if this external energy disappears, the electrons emit light in random directions while returning to their former orbits again. If they break off from orbits very close to the nucleus with a lot of energy and return here again, these lights are called “X-rays”. If we accelerate an electron beam with a voltage of about 30,000 V in a vacuum and hit it on a Tungsten surface, X-rays are emitted from the atoms here. In fact, we do not know the exact structure of electrons, and whether they are point particles, a wave packet or an energy group. There are neutral gases that we breathe in the atmosphere, such as ionosphere, stratosphere. But in the ionosphere there are plasma states of them. Since the ionosphere is the layer closer to space, it absorbs the energy of gamma or cosmic rays coming from space and transfers this energy to the atoms of the gases in the environment, turning these gases into + or - charged atoms, that is, “plasma”. Ions always tend to be neutral in nature, as this is the minimum energy state. In short, if an external influence comes, the atoms are charged and switch to a + or – ion state. After the external influence has disappeared, they immediately return to their former neutral state by emitting light. We call the gases charged in this way “plasma”.
In which sectors is it mainly used?
One of the sectors where plasma is used the most is “lighting”. Different types of gases are put into the ventilated bulbs, and the gas turns into plasma and begins to glow after giving off the energy. As is known, the powerful laser technology is widely used to affect surfaces. Powerful gas lasers are also obtained from plasma. If you place a reflective lens on one side of a long tube and a semi-transmissive lens on the other, and then a high voltage is applied at these points, the atoms will emit light only at certain wavelengths, and a laser beam will be formed. The intensity of these rays increases between the lenses, and then gradually increases as an amplifier. Eventually, a powerful laser beam will come out of the end of the tube. Plasma is also used for coating anything in the automotive and surface sectors. However, the applied voltage for these plasmas can be obtained by applying 10-20000V to the plates with only a few cm between them. With this kind of energetic plasma in atmospheric environments, you scan the material surface and the properties of the surface atoms change. For instance, it can be made suitable for coating or painting. For example, it completely eliminates the need for a paint primer and offers a super hold. On some surfaces, when the surface tension is reduced, the material may be able to absorb water or completely repel it. Textile surfaces that do not burn or absorb water are produced entirely by the plasma effect.
“We have established a plasma laboratory at TUBITAK that did not exist before.”
Can you tell us about the works you are doing with TUBITAK?
I want to make progress based on Mevlana’s philosophical words: "As a person ascends, his heart must descend." While I was receiving my doctorate from the US and serving my country, I tried to keep my arrogance and ambitions at bay, even as I rose in academic and industrial positions. Because I wanted to come out with my efforts and achievements instead of trying to put myself forward. Faculty members at universities usually go to TUBITAK and conduct research, studies, experiments and projects in a laboratory. The relationship between the universities and TUBITAK is established in this way. But I have established a plasma laboratory that did not exist before, with the support of several successful people working at TUBITAK. Now, there are advanced vacuum and measurement systems in that laboratory, and the laboratory is growing daily. We always try to get new ones and further improve them.
What would you like to say about vacuum technology?
We make vacuum boilers from stainless steel, but the work does not end there. As Türkiye, we need to make vacuum, diffusion and turbo molecular pumps. We can produce chips, integrated circuits and sensors with plasma made under vacuum. Vacuum, diffusion and turbo molecular pumps are extremely technological and expensive devices. We need to have companies that will be able manufacture them. We can manufacture compressors, but we import all the others. The main tactic of Europe and the US is to sell critical devices in those countries very cheaply in order to prevent the formation of technology in underdeveloped countries. In this way, you won't have to deal with it. Since you bought it cheaply, you will go back and buy it again after it loses its effect in a short time. This will contribute to the “exporter country”, not the “importer” one. There is an advanced vacuum system in our plasma laboratory at TUBITAK. Sensitive systems that perform prop and spectroscopic measurements inside the plasma and examine its properties have been purchased. In fact, producing such pumps does not come cheap and it may even cost more when calculated according to country’s currency rates. However, since the industrialists do not bother themselves and buy them directly, they think the issue is solved and when they start making money they stop producing them altogether.
“Plasma is also used for coating anything in the automotive and surface sectors. However, the applied voltage for these plasmas can be obtained by applying 10-20000V to the plates with only a few cm between them.”
How was plasma technology used during the pandemic period?
When we apply a high-voltage to the tube while draining the infected air and passing it through the tube, the air passing through this active energy environment turns into plasma and all kinds of bacteria and microorganisms in it are destroyed. This is actually what “sterilization” is. In this way, you release the air you have cleaned back into the environment, and microorganisms gradually decrease in the environment. There are also sterilization devices in operating rooms. They are placed in every 3-5 meters and clean the whole room before the operation is started. They absorb microbes, bacteria and micro-organisms in the air, destroy them and give the air back again. Dust particles traveling in the air, the skin hairs spilled from our bodies and the dust will also be removed.
How is Fusion Energy generated?
The disintegration of uranium by a neutron is called “fission”. If we can control this disintegration, nuclear reactors can be built. But if we release it into the environment uncontrollably, then it will become an “atomic bomb”. The fusion of deuterium and tritium into plasma is also called “fusion”. If we control this process, we make fusion reactors like Tokamak, but if we release them uncontrollably, we will make a “hydrogen bomb”. With these fusion reactors, thousands of times more energy will be generated than the nuclear power plants currently in use. I hope that one day TUBITAK will expand this established laboratory and start fusion studies. Since engines are not manufactured in Türkiye, the pumps used for thermal cycling in both fission and fusion energy are also imported. We need to establish motor factories and manufactures motors that can be used both in these power plants, electric vehicles and industrial automation systems. If we try to manufacture such critical devices, we need to do this steadily with very sound policies, in case we are blocked by exporting countries.
What would you like to say about ITER, the Latin for ”Way”?
The project we call ITER is the International Tokamak Fusion Reactors project developed by the Europeans. It is a bagel-shaped vacuum boiler and a system wrapped with superconducting wires, around which thousands of amperes of current pass. In Europe, both normal nuclear reactors and these Tokamak systems are operated. In other words, Europe has not completely abandoned nuclear as claimed. It is extremely important for us to enter into this technology and produce energy with nuclear rectors and make our energy cheaper. The nuclear reactor project, which has been started to be built in Mersin Akkuyu, is an extremely important project for our country. There is a certain amount of uranium in the Kaz Mountains. Also, there are the second most thorium reserves in the world at the bottom of the Northern Black Sea fault line. We can use thorium in conventional nuclear reactors. Fuels made with thorium are used in CANDU-type nuclear reactors. I believe that if one day we really uncover these resources and use them in nuclear technology, then we will have come a very long way. With these nuclear power plants, we can turn water into pressurized steam via nuclear energy and use it to turn the turbines, which are the motors we need to manufacture and generate electricity.
