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John Clarke, Michel H. Devoret and John M. Martinis received the Nobel Prize in Physics on Tuesday in Sweden for showing that two properties of quantum mechanics, the physical laws that govern the subatomic realm, can be observed in a system large enough to see with the naked eye.

“Today there is no advanced technology that is not based on quantum mechanics,” said Olle Eriksson, chairman of the Nobel Committee in Physics, during the prize announcement. The laureates’ discoveries, he added, paved the way for technologies such as mobile phones, cameras and fiber optic cables.

It also helped lay the groundwork for current attempts to build a quantum computer, a device that could calculate and process information at speeds that would not be possible with classical computers.

“This award really demonstrates what the American scientific system has done best,” said Jonathan Bagger, executive director of the American Physical Society. “It really showed the importance of investing in research that we don’t have an application for yet, because we know that sooner or later there will be an application.”

The three winners will share a prize of 11 million Swedish crowns, or about $1.17 million.

Why did you receive the award?

The three scientists were recognized for a series of experiments carried out in 1984 and 1985. They demonstrated the existence of two quantum phenomena in a system visible to the human eye.

The principles of quantum mechanics describe the strange properties and behaviors of single or small sets of elementary particles. In one such behavior, a particle can pass through a barrier even if it does not have enough energy to do so. This is called quantum tunneling and has only been confirmed on a very small scale.

Steven Girvin, a theoretical physicist at Yale University, compared the phenomenon of quantum tunneling to trying to drive a car in neutral up a hill. If the hill is too high, the car will not have enough power to reach the top. Instead, he stops and falls again.

The hill, he said, is like an energy barrier that the car cannot overcome.

“But if you were in a very small car and subject to the laws of quantum mechanics, even if you didn’t have enough energy to go up the hill,” he said, “you could still get to the other side through a process called tunneling.”

Another property of subatomic particles is that they can gain or lose energy only in fixed, discrete amounts. This is known as energy quantization.

However, with a large number of particles, these small quantum effects usually become negligible. (This is why humans, made up of millions of atoms, cannot pass through walls.) “We always think of quantum mechanics as a picture that applies to the level of individual electrons and atoms,” said Anthony Leggett, a physicist at the University of Illinois at Urbana-Champaign. In the 1970s, he and a graduate student predicted that quantum tunneling could be observed in a larger system. This year’s physics prize winners confirmed this prediction.

They showed, for the first time, that quantum tunneling is observable in a system they called macroscopic because it was “big enough to touch with dirty fingers,” according to their study. paper describing the discovery. They also showed that the energy of this system was quantized or existed at fixed levels.

“I’m very happy,” said Dr. Leggett, who won a share of the Nobel Prize in Physics in 2003. “I was hoping they would get a Nobel or something substantial for that work.”

The winners made their discoveries by studying a chip with a superconducting circuit, that is, capable of conducting current without electrical resistance. As a result, the current was “trapped” in a flow state without any voltage, because it did not have enough energy to escape, according to one study. summary published by the Nobel committee, as if he were behind a barrier that he cannot cross.

The researchers observed the current going from a zero-voltage state to a non-zero voltage state, an observation of quantum tunneling. They also observed that the system only absorbed light of certain frequencies, suggesting that its energy was quantized.

Who are the winners?

All three are professors at American universities. John Clarke, who studied at the University of Cambridge, has been a professor of physics at the University of California, Berkeley, since 1969. He is currently a professor emeritus in the university’s graduate school.

Yale’s Dr. Girvin referred to Dr. Clarke as “a godfather of superconducting electronics.”

Dr. Clarke is also collaborating with the Axion Dark Matter Experiment, which uses superconducting quantum devices to search for new types of particles in the universe.

Michel H. Devoret, who was born in Paris and received his Ph.D. there, he is professor emeritus of applied physics at the Yale School of Engineering and Applied Sciences. He is also a professor of physics at the University of California, Santa Barbara.

John M. Martinis has a Ph.D. from the University of California, Berkeley. After teaching at the university, he recently worked with Google’s quantum artificial intelligence team. He is also professor emeritus of physics at the University of California, Santa Barbara.

in a telephone interviewDr. Martinis explained that he had gone to bed early the night before the announcement, but that his wife had been up late. Around 3 a.m., he began receiving a flood of phone calls.

“My wife is very nice to me, so she didn’t wake me up for a couple of hours because she knew I needed to sleep,” Dr. Martinis said. “She did the right thing.”

At the time of the experiments, Dr. Clarke was the supervisor of Dr. Devoret, then a postdoctoral researcher, and Dr. Martinis, then a graduate student.

Dr. Martinis highlighted how important it had been to be part of this team at the beginning of his career and that he has been trying to reproduce the same spirit in his career ever since.

Dr. Clarke spoke by telephone to the Nobel committee during the prize announcement.

“To put it mildly, it was the surprise of my life,” he said of the recognition. “I’m completely stunned.” He added that it had never occurred to him that his discoveries “could be the basis of a Nobel Prize.”

“I couldn’t imagine accepting the award without the two of them,” Dr. Clarke said in a interview after the announcement.

At a press conference later that day at the University of California, Berkeley, Dr. Clarke emphasized the importance of basic scientific research. Widespread funding cuts over the past year “will cripple science,” he said, adding that if they continue, “it could take a decade to get back to where we were, say, half a year ago.”

What are the prospects for quantum computing?

There is a race in industry and academia to fulfill the promise of quantum computing, a strange and powerful technology.

A true quantum computer could accelerate the progress of drug discovery or other scientific research. It could also break encryption that protects computers vital to national security.

With so much interest in the applications of quantum mechanics, the work of Dr. Devoret and Dr. Martinis has gone beyond academia.

In 2014, Google hired Dr. Martinis and many of the researchers who worked alongside him at the University of California, Santa Barbara. At Google, he and his team built a machine that achieved what was called “quantum supremacy,” which was seen as a key milestone in the decades-long effort to build a viable quantum computer.

dr martinis left Google in 2020 and in 2022 he became co-founder of Qolab, a quantum computing startup.

Dr. Devoret is now the chief scientist of Google’s quantum computing division, as the tech giant competes with other labs to advance the technology.

Late last year, Google announced that it had built a quantum computer that took less than five minutes to perform a particularly complex mathematical calculation in a test designed solely to measure the technology’s progress. One of the world’s most powerful non-quantum supercomputers could not complete it in 10 septillion years, a time period that far exceeds the age of the known universe.

The technology remains experimental. But with tech giants like Google, Amazon and Microsoft and myriad startups like Qolab pushing the technology forward, many experts believe the technology will eventually fulfill its considerable promise, although this is still decades away.

Who won the Nobel Prize in Physics in 2024?

John J. Hopfield and Geoffrey E. Hinton shared the award for their work on discoveries that helped computers learn more in the same way the human brain does, providing the foundation for the development of artificial intelligence.

Who else has won a Nobel Prize this year?

Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi received the Nobel Prize in Physiology or Medicine on Monday for their discoveries about peripheral immune tolerance, the system that explains how the immune system prevents rogue cells from attacking tissues and organs.

When will the other Nobel Prize winners be announced?

The physics prize is the second of six Nobel Prizes to be awarded this year. Each award recognizes the innovative contributions of an individual or organization in a specific field.

• The Nobel Prize in Chemistry will be awarded on Wednesday by the Royal Swedish Academy of Sciences in Stockholm. Last year, the award went to Demis Hassabis, John Jumper and David Baker for work that showed the potential of artificial intelligence and other technologies to predict the shape of proteins and invent new ones.

• The Nobel Prize for Literature will be awarded on Thursday by the Swedish Academy in Stockholm. Last year, Han Kang, best known for her novel “The Vegetarian,” became the first South Korean writer to receive the award.

• The Nobel Peace Prize will be awarded on Friday by the Norwegian Nobel Institute in Oslo. Last year, the Japanese organization Nihon Hidankyo, a grassroots movement of atomic bomb survivors, received the award “for its efforts to achieve a world free of nuclear weapons.”

• Next week, the Royal Swedish Academy of Sciences will award the Nobel Prize in Economic Sciences in Stockholm on Monday. Last year, Daron Acemoglu, Simon Johnson and James Robinson were honored for their research into how institutions determine which countries become rich and prosperous, and how those structures came to exist in the first place.

All award announcements are broadcast live by the Nobel Prize organization.

Cade Metz contributed with reports.