Experiment shows spooky quantum action with superconducting qubits separated by 30 meters | technology

Quside/ICFO High purity and very fast quantum random number generator used during the experiment.
Quside/ICFO High purity and very fast quantum random number generator used during the experiment.Quside/ICFO

Physicist James Treville said that quantum mechanics is “an area of ​​the universe in which the human brain is not at ease.” And this discomfort is caused by nature, on a microscopic scale, responding to laws that challenge our understanding of macroscopic reality. Among these behaviors are superposition (a particle can be in different states at the same time, like Erwin Schrödinger’s cat alive and dead) and tele-entanglement or spooky action, as Albert Einstein described the principle that allows particles separated and remotely responding instantly and behaving as a single system. An amazing experiment that defies the speed of light, published Wednesday in nature By an international team of scientists, led by ETH (Swiss Federal Institute of Technology) in Zurich, in collaboration with Spanish entities ICFO (Institute of Photonic Sciences) and Quside, demonstrates for the first time this ghostly work in electrons separated by 30 meters with superconducting circuits, the most common systems in Quantum computing.

This experiment again contradicts Einstein, who considered quantum entanglement impossible. The physicist argued that each particle has certain properties in its environment, that action on it is generated in a specific place and its (local) consequences are transmitted. Against this theory, quantum physics has shown that two entangled particles share one unified state, even though, as in the case of the experiment in Zurich, they are 30 meters apart.

For Einstein, it was completely unacceptable for something in one place to have an immediate effect in another. But John Bell showed in 1964 that it does happen, and that quantum entanglement exists. Since then, experiments on this property have followed one another and results in this field by John Clauser, Alan Aspect and Anton Zellinger won the Nobel Prize in 2022.

See also  “Sandwich in 214″ or how apps can replace hotel reception to improve your experience | Your technology | Country

One of the greatest accomplishments of the experiment, published on Wednesday, is that it implemented proof of Bell’s theorem (or inequality) without Gaps An English term translated in quantum physics as loopholes. This absence of escape points to the fact that everything happens exactly as quantum physics predicts, and that communication between particles was not possible and does not respond to mere statistics.

An experiment involving the Spanish physicist Adán Cabello, from the University of Seville, achieved results along these lines with ytterbium and barium ions (Science advances) a year ago. But recent research shows the complication using two entangled superconducting qubits at temperatures near absolute zero (273.15 degrees Celsius) and 30 meters apart.

Defy the speed of light

Simultaneous measurements of the two qubits yielded consistent results about the state, and a simultaneous response consistent with phantom action at a distance or entanglement. To prove that there were no gaps, and that the coordination of states was not due to signals sent between qubits, random measurements were made at 17 nanoseconds, which is the time it takes light to travel five metres. A full measurement required another 62 nanoseconds (the latency of light at 21 m). Since the two systems were 30 meters apart, communication between them was impossible.

The research is key not only because it showcases quantum physics, but because it has practical applications. Morgan W. Mitchell, professor at the Catalan Institute for Research and Advanced Studies (ICREA) at ICFO and co-author of the study, explains that “with classic computers it is common to have computing on the web and for the results to reach your home machine”. He adds, “To do something equivalent with quantum computers, we need to connect them and it won’t be via conventional qubits. It has to be via qubits and this entanglement is the most efficient way to do that.”

See also  The appearance of the first home delivery robots in Spain | technology

This research shows that this kind of experiment can be done with superconductors, the systems used by Google or IBM. Other systems that were used were with a pair of particles. But this experiment created entanglement between a large number of electrons in this location and a large number of electrons in another location. It’s the first time this has been achieved without escape.”


The results allow, according to Mitchell, “advances in distributed computing, with many computers in several places.” He concludes, “This is a long-term goal that we won’t see right away, but this experience shows it’s possible.”

Carlos Abellan, co-author of the paper, Ph.D. in photonics from ICFO and co-founder and CEO of Quside (a company for the quantum components that were used in the experiment), highlights this, as well as the paradigm shift in a demo by scaling systems up to superqubits. Conducting, the work meant “the creation of an amazing and unique technology that was able to prove the synchronization of two particles at an unprecedented speed.”

The experiment required quantum random numbers (QRNG) to be generated and “extracted” at an extraordinary speed (17 nanoseconds) to rule out any possibility of communication between the qubits. “We had to develop a completely new architecture to be able to generate random numbers in such a way that we could do that before the information got to the other side. We needed to double the speed of the systems used before,” explains Abellan.

“What we did is, instead of using a single device and doing the math, we put eight devices in parallel in sync and combined the signal. In this way, we used 16 random number generators and were able to double the speed. If we took 19 nanoseconds instead of 17, the experiment wouldn’t be valid,” Add.

See also  Cyber ​​Attacks: Malware Reveals the Internet Security Paradox: Individual Defenses Against Global Threats | technology

The experiment proves that quantum information can be transmitted between separate superconducting circuits and placed in cooling systems, that is, it has been shown to happen and in systems already available for quantum computing. But it remains to be explained why this happens, and why two separate systems behave as if they were one. It’s a question of philosophy, very difficult. You can ask 10 different physicists and you will get 10 different answers. It is a mystery for other generations to solve. But what we can tell from these experiments is that they do exist,” says Mitchell.

You can write to it [email protected] and follow country technology in Facebook And Twitter Or sign up here to receive The weekly newsletter

Subscribe to continue reading

Read without limits

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button