Laser light can induce quantum behavior at room temperature and make non-magnetic materials magnetic
Quantum physics appears today in Hollywood films and even psychological treatises, but beyond science fiction, quantum theory explains how the fundamental components of matter work and promises the next quantum supercomputers.
The potential of quantum technology is enormous, but today it is largely limited to the extremely cold environments of laboratories. Now researchers from Stockholm University, the Nordic Institute for Theoretical Physics and Ca’ Foscari University in Venice have succeeded for the first time in showing how laser light at room temperature can induce quantum behavior and make non-magnetic materials magnetic. This advancement is expected to pave the way to faster and more energy efficient computers, information transmission and data storage.
Within a few decades, the advancement of quantum technology is expected to revolutionize several of the most important areas of society and pave the way for entirely new technological possibilities in communications and energy. Of particular interest to researchers in this field are the special and strange properties of quantum particles, which deviate completely from the laws of classical physics and can make materials magnetic or superconducting. By improving our understanding of exactly how and why these types of quantum states arise, the goal is to control and manipulate materials to obtain quantum mechanical properties.
From light to magnetism
Until now, researchers have only been able to induce quantum behavior such as magnetism and superconductivity at extremely cold temperatures. Therefore, the potential of quantum research remains limited to laboratory environments.
Now this research team is the first in the world to demonstrate in an experiment how laser light can induce magnetism in a non-magnetic material at room temperature. In the study published in Nature, researchers exposed the quantum material strontium titanate to short but intense laser beams of a particular wavelength and polarization to induce magnetism.
“The innovation of this method lies in the concept of allowing the atoms and electrons of this material to move in circular motions using light to create currents that make it as magnetic as a refrigerator magnet.” We have achieved this through the development of a new far-infrared Light source with “corkscrew” polarization successful. It is the first time that we have been able to induce in an experiment and clearly see how the material becomes magnetic at room temperature. Furthermore, our approach allows the production of magnetic materials from many insulators, while magnets are usually made from metals. In the long term, this opens up new applications in society,” says Stefano Bonetti, senior researcher at Stockholm University and Ca’ Foscari University in Venice.
The method is based on the theory of “dynamic multiferroicity,” which predicts that when titanium atoms are “shocked” with circularly polarized light in a titanium-strontium-based oxide, a magnetic field is created. But now the theory can be confirmed in practice. The breakthrough is expected to find wide application in various information technologies.
“This opens the door to ultra-fast magnetic switches, which can be used for faster information transmission and significantly better data storage, and to significantly faster and more energy-efficient computers,” says Alexander Balatsky, Professor of Physics at NORDITA.
In fact, the team’s results have already been reproduced in other laboratories, and a publication in the same issue of Nature shows that this approach can be used to write and therefore store magnetic information. A new chapter has opened in the design of new materials with light.
REFERENCE
Terahertz electric field driven dynamic multiferroicity in SrTiO3