SHANGHAI – More than a decade ago, Chinese physicist Pan Jian-Wei returned from Europe to help oversee research on some of the most important technologies in the 21st century. century.
They talked about the hacking-resistant communication networks they build all over China, the sensors they design to look through smog and around corners, and prototype computers that can one day crush the power of any existing machine.
All equipment is based on quantum technology – an emerging field that can transform information processing and provide major economic and national security benefits for countries that dominate it. To the dismay of some researchers and officials in the United States, China's formidable investment is helping to capture Western research in the field and in a few areas moving forward.
Beijing is pouring billions on research and development, offering Chinese scientists great benefits to return home from Western laboratories. China's drive has prompted calls for more R&D funding in the United States, and helped trigger concerns in the Trump administration that some types of scientific cooperation with China could help the people's liberation army and hurt US interests.
"The United States must be prepared for a future where its traditional technological predominance faces new, perhaps unprecedented, challenges," wrote the Center for a New American Security in a recent report on China's quantum ambitions.
Quantum technology seeks to exploit the different properties of atoms, photons and electrons to build more powerful information processing tools.
Last year, China had nearly twice as many patents as the United States for quantum technology in general, a category that includes communications and cryptology devices, according to market research firm Patinformatics However, the United States holds patents pertaining to the most valued segment – quantum computers – thanks to heavy investments from IBM, Google, Microsoft and others.
Helping oversee China's program is Pan, which Chinese media call "the father of quantum." From his labs at the University of Scienc e and Technology of China (USTC), in Shanghai and Hefei, the 49-year-old leads a team of 130 researchers. In 2017, the journal Nature pointed him to one of "ten people who mattered this year," and said he had "lit a guy during the country's quantum technology efforts."
Pan occasionally gives lab tours to President Xi Jinping, who is interested in his work, according to Chinese media. Pan also oversees the plans for a new national quantum research lab in Anhui Province, which he said had raised around $ 400 million in state funding.
At the Shanghai event, Pan illustrated his slideshow with science nerd jokes about Einstein and "Star Trek." In a nod to Schrödinger's cat – a 1930s thought experiment that helped define a quantum term called superposition – Pan used images of a cartoon cat standing and lying flat on its back.
"As we all know, In our everyday lives, a cat can only be in a living or dead state," Pan said, but "a cat in the quantum world can be in a continuous superposition of living and dead states. "
points out that quantum particles, also known as quantum bits, differ fundamentally from the bits of today's technology. Existing computers and communication networks store, process and transmit information by breaking it down into long streams of bits, which are typically electrical or optical pulses representing a zero or one.
Quantum bits, or qubits, which are often atoms, electrons or photons, can exist as zeros and at the same time, or in any position between, a flexibility that allows them to process information In some ways, some physicists compare them to a spinning coin that is at the same time in a head and tail state.
In his speech, Pan explained how China utilizes qubits to protect communications from hacking – one of the fields China appears to be having the lead over the West.
Pan and his team aim to launch a constellation of satellites and a nationwide fiber optic network that uses qubits for securely transmitting information. An almost 1,300-kilometer fiber link connecting Beijing, Shanghai and other cities is already underway. Then, a satellite China was launched in 2016, which has performed several prominent experiments, including the preparation of a hacking-resistant video conference between Beijing and Vienna.
Once the network is complete, it can complicate the United States' efforts to cancel China's government or military communications, some Western scientists say.
"I predict China will be black in two to three years – we can't read anything," said Jonathan Dowling, a physics professor at Louisiana State University who spends part of the year as a visiting faculty member at the USTC in Shanghai.  Others claim that even if China's network equipment is more secure, it can still be hacked by manipulating the people who operate the system.
If the technology gains traction globally, China may be in a strong position to sell it, given the large number of patents universities and companies have registered for devices and technology related to quantum communication and encryption, according to Patinformatics.
Pan credited Edward Snowden for motivating China's quantum research The former National Security Agency contractor's disclosures about NSA interception led to China pouring money into developing more secure communication, Pan has said in published interviews.
Barry Sanders, a Canadian physicist from the University of Calgary, spends two to three months a year. as a visiting professor at the USTC laboratories in Shanghai. He got the job through China's "Thousand Talents" program, which recruits Western scientists for teaching and research tips, and offers incentives to persuade Chinese scientists to return home from abroad.
Sanders said that China's cultural differences can provide benefits in the laboratory.
"I have my western way of doing things – freedom of thought, taking risks," he said. In China, there is more emphasis on the general public, he said. “One guy spent two years focusing on the lab room. You can assign people these tasks – they will do something that in our world will be seen as beneath us. But here they are supported and held in high regard. ”
Pan received his doctorate from the University of Vienna in 1999 and continued his research at the University of Heidelberg before moving home, along with several Chinese colleagues.
China's work on quantum technologies at that time was "relatively backwards" and needed outside help, Pan said in an email. "That's why our team took the initiative to send students to top research groups abroad to learn related technologies," he said. "Fortunately, they later returned to work in China."
Most of the Chinese scientists who spoke at the Shanghai Conference spent many years studying abroad. Their slide deck was peppered with humorous references to Western pop culture and events. One featured a photo of President Trump with the caption "Make SPDC Great Again" – a reference to an optical process where a photo is split in two. During a coffee break, a Chinese scientist's phone burst into a ringtone from the TV show "Friends."
Their doctorates or postdoctoral education came from universities such as Stanford, Massachusetts Institute of Technology, Cambridge and the University of Toronto, according to their biographies printed in the program.
While the talks did not focus on military applications, much of the technology they pursue will have clear uses in both the commercial and defense fields, researchers say.
Quantum machines may one day break all existing forms of encryption. Quantum sensors can help the Chinese military to track and target enemy troops with greater precision. The university where Pan works, USTC, has established several quantum research partnerships with state-owned defense companies in recent years, with goals that include improving the combat capabilities of naval vessels, according to Chinese media reports quoted in the Center for a New US Security Document.
"China's national advances in quantum communication and computing … will be leveraged to support military purposes," according to newspaper authors Elsa Kania and John Costello, who reviewed hundreds of Chinese-language media, government and technical reports.
Researchers who have discussed the field with US government officials say that the Trump administration has recently expressed concern about the number of Chinese students studying in the United States in sensitive areas such as quantum science.
"We have always encouraged the best and brightest to come from abroad, and it has always served our nation well," said John P. Reskill, Richard P. Feynman Professor of Theoretical Physics at the California Institute of Technology, who has informed the government on quantum technical issues. "But there is concern in the authorities about how we train all these people, and many of them are going back to China and competing for technologies that have implications for national security. And we're talking about what to do with it.
" Many of us in academia, even though we know there are complicated issues, tend to continue to encourage Chinese students to come, "Preskill said," but there are ongoing discussions in the government about what is the best policy to do so . "
In a poll this month, two US university associations said their members strengthened security protocols and built closer relationships with the FBI and intelligence agencies, after hearing" increasing concern "from the federal government about" foreign interference "in university research. They also praised the contributions of Chinese students and faculty, saying that the United States must continue to welcome them.
Pan said that he believed collaboration would only provide quantum science benefits.
"The academic exchange benefits both countries," he said via email. “I see no reason whatsoever for the US government to be concerned and discourage normal academic activity. Remember that quantum mechanics was first developed in Europe and then moved to the United States. "
When asked about his group contributing to research for the Chinese military, Pan said that his university and team are" by nature, for basic scientific research and education. "
" We publish our basic research results in international journals such as are available to read from around the world. From reading our newspapers, other people, who may be from the US, Europe, Japan or China, can be inspired and develop & # 39; immediately useful & # 39; technology or products for industry or commercial or military use, "he said, adding this was" beyond our control. "
Some corners of the US government restrict cooperation with China. In June, the Energy Department, one of the most important agencies that fund physics and quantum science research, banned its employees and entrepreneurs from responding to certain foreign talent recruitment programs, including China's one thousand talents. The agency said it wanted restrict "unauthorized transfer of scientific and technical information."
The ban followed the indictment of a former researcher at the Department of Energy's Los Alamos National Laboratory, on charges of having provided false statements about his involvement with a thousand talents.
"What we have said in brief is that you cannot work for the Department of Energy and for one of these foreign talent recruitment programs. You cannot work for a foreign country and the Department of Energy at the same time," said Chris Fall, director of the agency's Office of Science, in an interview.
Partially motivated by China's progress, Congress late last year passed the National Quantum Initiative Act, which provided more than $ 1.2 billion in research funding over five years. The Department of Energy is under pressure to receive a large portion of the money, which it plans to use to set up several quantum-focused research centers. The agency calls for ideas from its own national laboratories and from universities and the private sector when deciding how to establish these centers, Fall said.
"The great thing about how we conduct science in this country is that it is not top-down," he said.
For now, China is lagging behind the US technology industry in perhaps the most important race in the field: building a quantum computer.
A fully functioning quantum computer has the potential to be transformative. The exponentially greater computational power can help identify new chemical compounds for treating infectious diseases and eliminate traffic jams by predicting and controlling the flow of vehicles.
However, the possibility that the machines could eventually crack all existing forms of encryption is a major concern for militaries, authorities and businesses that handle sensitive data.
To get a fully functional computer – a goal that is a decade or more away, most researchers agree – researchers need to lure a large number of qubits to collaborate effectively. This is difficult because qubits are fine and tend to stop working at the slightest disturbance, such as a minor change in temperature.
Google and IBM are at the forefront and use superconducting circuits to manipulate qubits. Google unveiled a quantum processor of  72 qubits last year, surpassing IBM's previously announced 50 kBbit computer.
More important than the number of qubits is how effectively they work together, said Chris Monroe, a physicist from the University of Maryland and co-founder of the startup IonQ. The company recently reported that its prototype machine, using 11 qubits made from ionized atoms, performed more complex calculations with greater accuracy than any competing machine. (IonQ's investors include AWS, a subsidiary of Amazon, whose founder, Jeff Bezos, owns The Washington Post).
Chinese scientists have so far reported a 12-qubit processor using superconducting technology similar to Google's and IBM's.
The leader of this work, USTC professor Zhu Xiaobo, presented the team's results at the Shanghai conference and flashed a picture of their prototype on the screen – a shiny bunch of coaxial cables resembling an intricate golden chandelier. (IBM and Google machines have a similar look.)
"We are now working on 24 qubits," Zhu said. "We hope we get to 50 next year, and maybe someday we get to quantum superiority," he added, referring to the point where a quantum computer can perform a calculation that existing computers cannot. Although the reference is expected, scientists will only mark the beginning of progress, say researchers.
Lu Chaoyang, a young physicist who received his doctorate at Cambridge University, also went to the lecturer to provide an update on the team's approach to quantum computation. It relies on photons, which he called "fast-flying qubits."
Although the idea of a quantum computer first appeared 40 years ago, it's still a long way to go, Lu said.
He then pressed playback on a short video piece by "Harry Potter" author JK Rowling, who talked about the importance of setting "achievable goals."
"It is important that we set achievable goals for experiments so that we can continuously move forward," Lu said.
Lyric Li contributed to this report .