Scientists prove 'quantum theory' that could lead to ultrafast magnetic computing

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Superfast magnetic memory devices are possible after scientists engineer way to use lasers to magnetize non-magnetic materials.

A futuristic image of a computer chip
By inducing a "switchable" magnetic field, scientists have induced a quantum property that could pave the way for faster computing. (Image credit: Yuichiro Chino via Getty Images)

For the first time, scientists have magnetized a non-magnetic material at room temperature, inducing a quantum property that they say could pave the way for ultra-fast computing.

The "switchable" magnetic field could one day be used to store and transmit information. This was something previously only possible at ultracold temperatures.

The results pave the way for "ultra-fast magnetic switches that can be used for faster information transfer and considerably better data storage, and for computers that are significantly faster and more energy-efficient,” study lead author, Alexander Balatsky, professor of physics at the Nordic Institute for Theoretical Physics (NORDITA), said in a statement.

Scientists have long wanted to harness the weird laws of quantum mechanics to improve computing systems, for example in quantum computing. But quantum states are delicate, and can easily fall apart, or "decohere," thanks to noise such as thermal vibration, or the random jiggling of atoms. 

Related: Weird magnetic 'skyrmion' quasiparticle could be used as a bit in advanced computing memory

To get around this, researchers aiming to create quantum behavior typically cool their materials to near absolute zero. But that makes such systems difficult to maintain and operate.

In 2017, Balatsky and colleagues laid out a theoretical approach to generating a quantum state, called "dynamic multiferroicity," in which electrical polarization induced magnetism in a non-magnetic material. The process involves stirring up titanium atoms in a material in such a way that they generate a magnetic field. 

Stefano Bonetti in his lab at Stockholm University

Stefano Bonetti was one of the scientists at Stockholm University who worked on the technique. (Image credit: Knut and Alice Wallenbergs Foundation/Magnus Bergström)

In the new study, published April 10 in the journal Nature, Balatasky's team demonstrated the theory in titanium atoms surrounded by strontium titanate — an oxide created from titanium and strontium. The team transmitted laser pulses that generated circularly polarized photons, or light particles, in a narrow band of wavelengths.

The researchers fired the 1,300-nanometer wavelength infrared laser at the material in femtosecond (a quadrillionth of a second) bursts of 800 microjoules; by comparison, lasers used in hair removal are up to 40 joules – or 40,000,000 microjoules. They focused the pulses onto the material using three parabolic mirrors to create a rounded beam approximately 0.5 millimeters in diameter.

These pulses induced circular motion in the atoms within the material. When left-circularly polarized, the north pole of magnetization pointed upwards, but when right-circularly polarized, the north pole pointed downwards, creating magnetic fields as strong as a refrigerator magnet that can be switched on and off. The magnetic field existed only while the atoms were stirred.

The researchers envision this breakthrough leading to ultrafast magnetic switches that can operate at room temperature — using lasers to control the lattice vibrations of a material. This system could be the basis for transistors in smaller and faster computing systems that no longer require cold temperatures to operate.

This is not the first time scientists have used light to harness the power of magnetism for computing. In January, a separate study used the magnetic component of light to manipulate the magnetism of a solid material, which could lead to ultrafast magnetic computing memory components in the future.

Peter Ray Allison
Peter Ray Allison

Peter is a degree-qualified engineer and experienced freelance journalist, specializing in science, technology and culture. He writes for a variety of publications, including the BBC, Computer Weekly, IT Pro, the Guardian and the Independent. He has worked as a technology journalist for over ten years. Peter has a degree in computer-aided engineering from Sheffield Hallam University. He has worked in both the engineering and architecture sectors, with various companies, including Rolls-Royce and Arup.