This can make the world's fastest computers slow

NTNU has many talented researchers. Some of them are working on new ways to transmit information more efficiently. They often do this because they find it exciting, but a nice side effect is that their work can contribute, for example, to faster computers that use less energy.

One of these is Therese Frostad.

“I work with spintronics, a research field that uses electron spin to develop new technology,” says Frostad, a researcher in the Department of Physics at NTNU.

If you don't understand the previous sentence, don't worry, because we can solve it together. Come here!

Spin transmits information

An electron is a charged particle in an atom. Electricity is actually just electrons moving along matter.

In ordinary computers and other electronics, information is transmitted precisely with the help of electricity, i.e. electron flow.

But heat generation is a problem because computers are getting faster and because components are getting smaller and closer together, Frostad says.

So the conventional technology is approaching its limit. Therefore, researchers search for new ways to transmit information. One solution is to take advantage of the spin of electrons, as Frostad does. So what is this rotation at the moment?

Electrons have spin

In addition to charge, electrons have another property called spin. This, among other things, is the basis of magnetism.

Physicists like Frostad can manipulate this spin with the help of magnetic fields, changing the spin so that the change moves like a wave through the atoms in the material.

In spintronics, we can use spin waves as information carriers, Frostad says.

These spin waves produce much less heat than electron currents. Thus this could be a solution to heat generation in conventional electronics.

– It could also help us develop technology with low energy use, says Frostad.

Bose-Einstein condensates

During his PhD, Frostad worked with Bose-Einstein condensates, which are more exciting than you think once you know what they are.

The strangest things happen in Bose-Einstein condensates, at least if you see them with the eyes of a non-physicist.

For example, a few years ago a group of researchers was able to reduce the speed of light to just over 60 kilometers per hour in Bose-Einstein condensates. Then the bravest can navigate from the light to the cliff. It is difficult to do this under normal circumstances, even if you train hard. But what are these capacitors?

Most people know that a substance can be a solid, liquid, or gas. In addition, there is plasma, a type of gas with charges. So Bose-Einstein condensates exist, but no one was sure about that until a few years ago.

The theory behind these condensates was the brainchild of Indian physicist Satyendra Nath Bose, who included superstar Albert Einstein on the team to publish the first research paper on them. This year is actually 100 years since the two began their collaboration, but no one actually found such condensates until 1995. Atomic condensates only occur at extremely low temperatures, close to absolute zero.

Physicists often like Bose-Einstein condensates because they are well suited for studying magnetic fields, gravity, and the fundamental properties of matter.

You can also study spin waves in Bose-Einstein condensates, which is what Frostad did.

Magnons – a spinning wave

“We like to call a spin wave “crazy,” says Frostad.

The singer is also what is called a “boson”, which is one of the two groups of particles that physicists talk about in quantum mechanics. Now we are at the nano level and quantum mechanics fields.

– When magnons assemble in the lowest energy state, they can form a Bose-Einstein condensate themselves, Frostad says. – This is exciting, and we have recently started investigating whether we can use magnon capacitors in new technology.

Perhaps researchers can contribute to the development of quantum computers where magnon condensates are part of the technology.

Engineered magnon capacitors

But if we're going to use magnon capacitors for something useful, we must first learn to control the properties of the capacitors, Frostad says. – This was the purpose of research for my doctoral thesis.

During her work, she made theoretical calculations regarding how madrons are created and how condensed madrons interact with and influence each other.

– We studied how we can control the properties of capacitors through external magnetic fields and how we can change the properties of the materials and systems in which we made the capacitors.

It can be useful in several areas

Frostad's supervisor was Professor Arne Bratas at the Department of Physics at NTNU.

The research expands the possibility of controlling Bose-Einstein condensates. Perhaps this could be used in future quantum sensing technology, Pratas says.

He receives support from Frostad's partner, researcher Alireza Qayyumzadeh at NTNU's Department of Physics.

One of the advantages of magnon capacitors is that they can exist at room temperature. In the future, he says, perhaps Magnon-Bose-Einstein condensates could be used as sensitive detectors in basic science.

Basic science will make us understand more about the basic mechanisms behind various natural phenomena. No one knew what lasers were for when they were invented either, Qayyumzadeh recalls. You don't always know what will be useful.

“Maybe we can imagine that this could be used to detect the dark matter of axions,” says Qayyumzadeh.

No, I have no idea what the latter means either. But this is about very basic physics, i.e. how the world around us works. Which is great anyway.

The article was first published on Gemini.No