Quantum computers may be destroyed by high-energy particles from space

 Radiation from space might be an enormous problem for quantum computers because cosmic rays can disturb their fragile inner workings and limit the sorts of calculations they will in the future perform.

Quantum computers are products of quantum bits, or qubits, which are accustomed store and manipulate quantum information. When designing qubits, one of all the foremost important factors is that the coherence time, which is that the amount of your time a qubit can remain during a particular state.

“The longer you've got, the more calculations you'll be able to do, the more complex calculations, and therefore the more reliable those calculations are,” says Brent VanDevender at the Pacific Northwest National Laboratory (PNNL) in Washington state. “Even some milliseconds isn't really long enough to try and do general-purpose quantum computing.”

He and his colleagues used two qubits to check what proportion of radiation within the environment affects the coherence time of a sort of qubit supported superconductors. Superconductors use pairs of electrons to hold a charge, but previous experiments have shown that those pairs are split apart way more often than expected, which lowers coherence time.

The researchers found that background signal, both from nuclear decay events that happen naturally all told forms of materials and from cosmic rays that penetrate everything, can account for all those extra broken pairs of electrons.

That radiation isn’t an issue for quantum computers yet because there are other sources of noise that are more prevalent, they say, but as quantum computers reclaim over the following decade, it might be a limiting factor. a number of the radiation are often stopped by employing a lead or concrete shield around the computer or placing it underground like physicists do with other experiments that are sensitive to cosmic rays.

However, if quantum computing is to become more widespread, the concept of putting all the computers underground “starts to induce ludicrously and becomes an argument for other forms of qubits”, says VanDevender. Instead, he and his colleagues are working to create qubits that will tolerate some broken electron pairs without losing their coherence.

That could have a surprising benefit for other physics experiments, which have detectors that hunt for radiation caused by matter particles or neutrinos. These often need high sensitivity to broken electron pairs. “If you'll be able to design a qubit that's less sensitive to those broken pairs, you'll almost certainly design a physics detector that's more sensitive,” says Ben Loer, also at PNNL, who worked on the study.