In a new breakthrough, researchers from the University of Copenhagen in collaboration with Ruhr University Bochum have solved a problem that has been a headache for quantum researchers for years. Researchers can now control two quantum light sources instead of one. While trivial to those unfamiliar with quantum theory, this tremendous breakthrough allows researchers to create a phenomenon known as quantum mechanical entanglement. This opens new doors for companies and others to use technology commercially.

Going from one to the other is a minor achievement in most contexts. But it is very important in the world of quantum physics. For years, researchers around the world have sought to develop stable quantum light sources and realize a phenomenon known as quantum-mechanical entanglement, a phenomenon with almost science fiction-like properties, in which two light sources can interact with each other instantly and potentially over large areas. . Geographical distances Entanglement is the foundation of quantum networks and is central to the development of an efficient quantum computer.

Researchers from the Niels Bohr Institute have just published a new result in the highly respected journal. Science, they succeeded. According to Professor Peter Lodal, one of the researchers behind the result, this is an important step in an attempt to take the development of quantum technology to the next level and “quantize” society’s computers, encryption and the Internet.

“We are now able to control two quantum light sources and connect them together. This may not seem like much, but it is an important advance and builds on the last 20 years of work. Professor Peter Lodahl, who has been researching in this area since 2001, said: “In this way, quantum hardware is the most “We’ve unlocked the key to scaling technology that’s so important to its innovative applications.”

Quantum resources surpass the world’s most powerful computer

Peter Lodahl’s group is working with a type of quantum technology that uses light particles called photons as microcarriers to carry quantum information.

Although Lodahl’s group is a leader in this discipline of quantum physics, they have so far only been able to control one light source at a time. This is because light sources are extremely sensitive to external “noise”, so copying them is very difficult. In their new results, the research team was able to create two identical quantum light sources instead of one.

“Entanglement means that by controlling one light source you immediately affect the other. This makes it possible to create a whole network of entangled quantum light sources that interact with each other, just like bits in a normal computer, where you can only perform much more powerful quantum bit operations,” explains the postdoctoral student. researcher Oleksiy Tyranov, lead author of the article

This is because a quantum bit can be both a 1 and a 0 at the same time, leading to computing power not available with modern computer technology. According to Professor Lodal, just 100 photons emitted by a single quantum light source will contain more information than the world’s largest supercomputer can handle.

Using 20-30 entangled quantum light sources, there is the potential to create a universal error-correcting quantum computer, the ultimate “holy grail” of quantum technology, in which large IT companies are currently investing billions.

Other actors will rely on research

The biggest challenge, according to Lodahl, was controlling one to two quantum light sources. Among other things, this has led researchers to develop ultra-quiet nanochips and have precise control over each light source.

Fundamental research in quantum physics is now in place, thanks to a new research breakthrough. Now is the time for others to take the work of researchers and use them in their quest to embed quantum physics into a range of technologies, including computers, the internet, and encryption.

“It is very expensive for a university to set up a facility where we will control 15-20 quantum light sources. So now that we have contributed to the understanding of fundamental quantum physics and have taken the first step along the way, further expansion is a very technological challenge,” says Professor Lodahl.