Oxford links strontium and calcium atoms, keeping entanglement for 10 seconds

[BretHart_Mike]

University of Oxford physicists have entangled atoms of two different elements, strontium and calcium, across a quantum network. Quantum Zeitgeist covered the work, which is published in Physical Review Letters. The team created shared entangled states involving up to four atoms of the two species

The idea is to use each element for what it does best. Strontium ions are good at creating network links, because they interact well with light. But the entanglement they hold usually lasts only milliseconds. Calcium ions are less sensitive to magnetic field noise, so they make better memories

By transferring the entanglement from strontium to calcium, the team extended its lifetime to more than 10 seconds. That is an enormous improvement, several thousand times longer than the strontium alone could manage

Lead author Dougal Main explained that having more than one type of atom in a quantum computer lets you take the best properties from each. Co-author Gabriel Araneda pointed to uses in networked quantum computing, remote sensing and comparing different types of atomic clocks

Oxford has been a leader in trapped ion networking for years, and this result builds nicely on that work. Mixing species is a key step towards modular quantum computers, where separate processors are linked together and each part does the job it suits best. It is the kind of patient engineering that makes scaling possible

Will future quantum computers routinely use more than one type of atom? And how important are long lived network links for scaling?

Strontium Links Atoms, Calcium Preserves Entanglement For Longerquantumzeitgeist.com