Physicists demonstrate 3,000 quantum-bit system capable of continuous operation

An often repeated example illustrates the mind -boggling potential of quantum computers: a machine with 300 quantum bits could simultaneously store more information than the number of particles in the known universe.

Now treat this: Harvard scientists have just unveiled a 10 -time larger system and the first quantum machine capable of operating continuously without restart.

In an article published in the journal NatureThe team has demonstrated a system of more than 3,000 quantum bits (or qubits) which could operate for more than two hours, on the overcome of a series of technical challenges and representing an important step towards the construction of super computers, which could revolutionize science, medicine, finance and other areas.

“We have demonstrated the operation continues with a 3,000 qubit system,” said Mikhail Lukin, Joshua and Beth Friedman University Professor and Codirector of Quantum Science and Engineering Initiative, and the main author of the new newspaper. “But it is also clear that this approach will also work for much more important figures.”

The collaboration led by Harvard included MIT researchers and was jointly managed by Lukin, Markus Greiner, George Vasmer Leverett Professor of Physics, and Vladan Valétic, Leter Wolfe professor of physics at MIT. The team is carrying out research in collaboration with Quera Computing, a start-up company transformed by Harvard-Mit Labs.

Conventional computers code the information – from a video to your phone to the words and images of this page – in bits with a binary code. Quantum computers use subatomic particles in individual atoms and take advantage of the counter-intuity properties of quantum physics to obtain much more treatment power.

Binary conventional bits store information as zeros or. The qubits can be zero, one or both at the same time – and this linear combination of amplitudes is the key to the power of quantum computers.

In conventional computers, the doubling of the bits doubles the power of treatment; In quantum computers, the addition of qubits exponentially increases power due to a process called quantum tangle.

But the realization of major quantum systems has posed major challenges.

Neutral atom systems (those who do not have an electrical load because they have an equal number of protons and electrons) have become one of the most promising platforms for quantum computers.

But an obstinate problem was the “loss of atoms” – the qubits escaping and losing their coded information. This gap has experiences limited to efforts in a blow in which researchers must take a break, recharge the atoms and start again.

In the new study, the team designed a system to continuously and quickly replenish the qubits using “optical network conveyors” curves that transport atoms) and “optical tweezers” (laser beams that grasp individual atoms and organize them in grid tables). The system can recharge up to 300,000 atoms per second.

“We show a way where you can insert new atoms because you lose them naturally without destroying the information already in the system,” said Elias Trapp, co-author of paper and doctorate. Student at Kenneth C. Griffin School of Arts and Sciences Student Physics. “It really solves this fundamental strangulation neck of loss of atoms.”

The new system has exploited a range of more than 3,000 qubits for more than two hours – and in theory, have said that researchers could continue indefinitely. More than two hours, more than 50 million atoms had traveled the system.

Lukin added: “This new type of continuous operation of the system, involving the capacity to quickly replace lost qubits, can be more important in practice than a specific number of qubits.”

In follow -up experiences, the team plans to apply this approach to carry out calculations.

NEG-CHUN Chiu, principal author of the study and a pH.D. of Harvard Griffin. The student in physics, said: “What really brings us out is the combination of three things: the scale, the preservation of quantum information and the appointment to the whole process to be useful.”

The new study advances a rapidly developing research border. In fact, this week, a Caltech team published a system of 6100 qubit, but it could only work less than 13 seconds.

In another article also published in NatureThe Harvard-Mit team has demonstrated an architecture for reconfigurable atoms to simulate exotic quantum magnets.

The approach makes it possible to modify the connectivity of the processor during the calculation process. On the other hand, most existing computer fleas – such as your mobile phone or office – have fixed connectivity.

“We can literally reconfigure the atomic quantum computer during its operation,” said Lukin. “Basically, the system becomes a living organism.”

In a third article published in NatureThe team demonstrates a quantum architecture with new error correction methods. With this new research set, Lukin believes that it is now possible to envisage quantum computers that can perform billions of operations and continue to operate for days.

“Realizing this dream is now at our direct sight for the first time, never,” he said. “We can really see a very direct path to the realization.”

This story is published with the kind authorization of the Harvard Gazette, Official Journal of Harvard University. For more new academics, visit Harvard.edu.