Quantum States last only a few millionths of a second, and simple methods can extend them by 10000 times

Sina science and technology news Beijing time on August 19 news, in the field of quantum science, some simple innovation may bring more possibilities. If we can manipulate quantum technology, human life may change dramatically. But first, scientists have to make quantum systems last longer, not just a few millionths of a second. < / P > < p > researchers at the University of Chicago’s Pritzker School of molecular engineering have announced that they have found a simple adjustment method that can make the running time – or “coherent” time – of a quantum system 10000 times longer than before. The researchers tested the technology on a special quantum system called “solid-state qubits”, but they believe that the technology should be able to be applied to many other types of quantum systems, potentially revolutionizing quantum communication, computing and sensing technologies. The results of the study are published in the August 13 issue of science. < / P > < p > “this breakthrough lays the foundation for quantum science research and opens up exciting new avenues for quantum science research,” said David awschalom of the College of molecular engineering. “The wide applicability of this discovery, coupled with a very simple implementation method, makes this strong coherence affect many aspects of quantum engineering. There are also opportunities for studies that were previously considered impractical. ” Osalom is also a senior scientist at Argonne National Laboratory and director of the Chicago quantum exchange. The world operates at the atomic level according to the rules of quantum mechanics, which is quite different from what we see in our daily life. These rules can be transformed into very futuristic new technologies, such as non intrusive networks or extremely powerful computers. On July 23, the U.S. Department of energy released a blueprint for the future of quantum Internet at the University of Chicago. However, researchers still have to face the most basic engineering challenge: quantum states need to operate in an extremely quiet and stable space, because they are easily disturbed by background noise such as vibration, temperature changes or stray electromagnetic fields. As a result, scientists are trying to find a way to keep the coherent state of the quantum system as long as possible. A common method is physical isolation, that is, to isolate quantum systems from noisy environments by physical means, but this method can be very cumbersome and complex. Another technique is to make sure that all the materials in the quantum system are as pure as possible, but it’s very expensive to do so. Researchers at the University of Chicago took a different approach. < / P > < p > “in this approach, we’re not trying to eliminate noise in the environment,” said Kevin Miao, a post doctoral researcher and lead author of the paper. “On the contrary, we ‘cheat’ the system to think it’s not affected by the noise.” < / P > < p > the team used additional continuous alternating magnetic fields, combined with commonly used electromagnetic pulses, to control quantum systems. By precisely adjusting this magnetic field, researchers can accelerate the spin of the electrons, allowing the system to “shield” the rest of the noise. < / P > < p > “the principle is to sit on a carousel and everyone around you is yelling,” explains Kevin Miao. “When the horse is stationary, you can hear the noise clearly, but if you rotate quickly, the noise will blur and become the background.” The small adjustment of < / P > < p > keeps the coherent state of the quantum system for 22 ms, which is four orders of magnitude higher than that of the unmodified system, and is much higher than that of the previously reported electron spin system. As a reference, we blink for about 350 milliseconds. This quantum system can almost completely shield some forms of temperature fluctuations, physical vibration and electromagnetic noise, which will destroy the quantum coherence. < / P > < p > the researchers say this simple adjustment may push quantum technology to make new discoveries in almost all fields. “This approach opens up a way to scalability,” oshalom said. “With this approach, it will be possible to store quantum information using electron spin. Extending the storage time will enable quantum computers to perform more complex operations and enable quantum information transmitted by spin devices to travel longer distances in the network < / P > < p > although the researchers tested in solid-state quantum systems using silicon carbide, they believe that the technology should have similar effects in other types of quantum systems, such as superconducting qubits and molecular quantum systems. This level of versatility is unusual for an engineering breakthrough. < / P > < p > “there are a lot of candidate quantum technologies that have been abandoned because they can’t maintain quantum coherence for a long time,” says Kevin Miao. “Now that we have this method to significantly increase the time to maintain coherence, we can reassess these coherences.” The most exciting thing, he added, is that it’s very easy to do, “the science behind it is complex, but the logic of adding an alternating magnetic field is very straightforward.”. (Ren Tian)