The global race towards a functioning quantum computer is on. With future quantum computers, we will be able to solve previously impossible problems and develop, for example, complex medicines, fertilizers, or artificial intelligence.
The research results published today in the scientific journal, Nature Communications, suggest how harmful errors in quantum computing can be removed. This is a new twist towards a functioning quantum computer.
Even a quantum computer needs cooling fins
How quantum computers differ from the computers that we use is that instead of computing using normal bits, they use quantum bits, or qubits. The bits being crunched in your laptop are either zeros or ones, whereas a qubit can exist simultaneously in both states. This versatility of qubits is a needed for complex computing, but it also makes them sensitive to external perturbations.
Just like ordinary processors, a quantum computer also needs a cooling mechanism. In the future, thousands or even millions of logical qubits may be simultaneously used in computation, and in order to obtain the correct result, every qubit has to be reset in the beginning of the computation. If the qubits are too hot, they cannot be initialized because they are switching between different states too much. This is the problem Mikko Möttönen and his group have developed a solution to.
A refrigerator makes quantum devices more reliable
The nanoscale refrigerator developed by the research group at Aalto University solves a massive challenge: with its help, most electrical quantum devices can be initialized quickly. The devices thus become more powerful and reliable.
“I have worked on this gadget for five years and it finally works!” rejoices Kuan Yen Tan, who works as a postdoctoral researcher in Möttönen’s group.
Tan cooled down a qubit-like superconducting resonator utilizing the tunnelling of single electrons through a two-nanometer-thick insulator. He gave the electrons slightly too little energy from an external voltage source than what is needed for direct tunnelling. Therefore, the electron captures the missing energy required for tunnelling from the nearby quantum device, and hence the device loses energy and cools down. The cooling can be switched off by adjusting the external voltage to zero. Then, even the energy available from the quantum device is not enough to push the electron through the insulator.
“Our refrigerator keeps quanta in order,” Mikko Möttönen sums up.
Next, the group plans to cool actual quantum bits in addition to resonators. The researchers also want to lower the minimum temperature achievable with the refrigerator and make its on/off switch super fast.
Artistic impression of the quantum-circuit refrigerator in action. As an electron tunnels, it simultaneously captures a photon from a quantum device, which leads to cooling of the device. Image: Heikka Valja
Watch the quantum physicists explain the operating principle of the refrigerator in two minutes using a sledge and a hole in the ice.
Learn more: Refrigerator for quantum computers discovered
The Latest on: Quantum computing
Google wants to make programming quantum computers easier
on July 18, 2018 at 4:17 pm
Its new open-source software will help developers experiment with the machines, including Google’s own super-powerful quantum processor. Quantum computers are still in their infancy, but builders of t... […]
Quantum computing supremacy would be a ‘digital nuclear bomb,’ Rep. McCaul says
on July 18, 2018 at 9:33 am
The chairman of the House Homeland Security Committee minced no words Wednesday about the ongoing global arms races to develop quantum computing, saying the country that harnesses it would have a rema... […]
Q&A with Microsoft's Jerry Nixon: Quantum Computing and the Future of Software Development
on July 17, 2018 at 12:06 pm
Quantum computing is just too far out there for many developers. Even Jerry Nixon, an expert on the topic, admits it sounds a lot like something right out of Star Trek. But Nixon, a developer evangeli... […]
Is China Set to Dominate over America in Quantum Computing and Artificial Intelligence?
on July 17, 2018 at 10:57 am
Washington is shifting its attention to strategic technology competition with Beijing. While long pushed in the Pentagon, other government branches like Congress, federal departments and even lobbyist... […]
IBM’s Dario Gil will showcase quantum computing progress at Disrupt SF
on July 17, 2018 at 9:03 am
After a few quiet years, the hype around quantum computing is reaching a new crescendo. Quantum supremacy now feels like an achievable goal. Among the large tech firms, IBM — and specifically the IBM ... […]
via Google News and Bing News