Quantum computing for a long time seemed a distant technology that might be realized in twenty years. But 2017 could be the year when the most daring ideas of scientists will be implemented.
Computer giants Google and Microsoft recently hired a lot of outstanding scholars and set before them the difficult challenges this year. The ambitious plans of the companies are to finally move from theory to practice.
In 2014, Google began work on a device for quantum computing, which uses superconductivity. Scientists hope that this year or more later they will be able to perform calculations that are not under the power of the most powerful “classical” supercomputers. Their competitor – Microsoft – relies on an intriguing, but unproven yet the concept of topological quantum computing and hopes to be the first to introduce it to the public.
Startups working in quantum computing are also involved in the race. Physicist Robert Schoelkopf from Yale University (new haven, CT), co-founder of a startup Quantum Circuits, and a former IBM physicist Chad Righetti (Berkeley, CA) expect to commit a breakthrough in the near future.
In the academic laboratories of the same opinion. Robert Schoelkopf steering group, which is engaged in the construction of a quantum computer at Yale, said that they checked all the components and features. He and many other scientists agree that although you need to spend a lot of physical experiments, the main difficulties now are in engineering. A quantum computer with the greatest number of cubits (20 cubits), and was now being tested at the University of Innsbruck in Austria under the leadership of Reiner Cronyism.
While ordinary computers encode information by means of bits which can be in two States – zero or one – “qubits”, which are quantum computers can be in “superposition” of two States at once. This, as well as the ability of qubits to be in quantum state called confusion, will allow computers to perform many calculations simultaneously. And, in principle, the number of calculations is doubled for each additional qubit, leading thus to an exponential increase in performance.
This speed could allow quantum computers to perform certain operations such as searching vast databases, or the factorization of large numbers, which would be impossible for slower computers. Quantum computers could also be used as study tool: chemists would be able to simulate chemical reactions or physics is to develop superconductive materials.
There are many opinions about how to build qubits. Among them are two approaches that have demonstrated the ability to store information for a long time in spite of the vulnerability of quantum States against external influences. The first approach, developed by Schoelkopf and adopted by such companies as Google, IBM, and Rigetti Quantum Circuits is to encode quantum States as oscillatory currents in the superconducting loops. The second approach, developed by the IonQ and several major academic laboratories is to encode qubits in single ions are held by electrical and magnetic fields in vacuum traps.
Physicist John martinis, who has worked at the University of California before Google hired him and his research group in 2014, said that more detailed knowledge of the technology of superconductivity suggested his team bold idea of quantum superiority.
A team of scientists plans to achieve it with the help of chaotic quantum algorithm that creates what seems like a random output. If the algorithm runs on quantum computer from a relatively small number of qubits, an ordinary computer can predict the outcome. But as soon as the quantum machine is approaching the use of fifty cubits, even the largest classical supercomputers will not be able to keep up with it.
The calculation results will have practical application, but they show that there are tasks, with which the strength to cope only quantum computers, and it will attract the attention of potential customers.”We think it will be a fruitful experiment,” says martinis.
But Robert Schoelkopf does not consider the idea of the quantum of the superiority of something interesting or useful. This is partly due to the fact that there is the problem of error correction: the system’s ability to recover deteriorates with increasing number of qubits. Instead, the startup Quantum Circuits focused on from the beginning to create a machine that does not require error correction.
Christopher Monroe hopes to achieve quantum supremacy in the near future, but it is not the main goal IonQ. According to him, the idea of a startup lies in the construction of machines, which will have 32 or even 64 qubit and the ion trap technology will allow their designs to be more flexible than superconducting circuits.
Microsoft, meanwhile, is betting on a different technology. Topological quantum computation depend on the substance that encodes information by obfuscation like braids. Information stored in these qubits will be more resistant to external influences, but also facilitate the correction of errors.
So far no one has managed to create such structures. But Microsoft has attracted four leading scientists, including Leo Kouwenhoven from the University of Delft in the Netherlands.
“I tell my students that 2017 is the year of braiding,” said Kouwenhoven involved in the construction of the laboratory Microsoft in Delft.
Other scientists are more cautious in their forecasts. “I don’t do press releases about the future,” says Rainer Cronyism. A physicist from the National Institute of Standards and Technology (boulder, Colorado) David Vineland, who heads the work on ion traps, also does not want to give any predictions. “I’m optimistic in the long term, but how long it will be, I don’t know,” the scientist said.