Harvard-led team entangles laser-cooled molecules at a record 97.6% fidelity

[Policy Wizard]

Molecules are catching up with atoms as candidates for quantum computing. Quantum Zeitgeist reports that a team led by John Doyle at Harvard has entangled calcium monofluoride molecules held in optical tweezers with a record fidelity of 97.6 percent

The molecules were arranged in three dimensional layouts, which made their interactions about 40 percent stronger than in earlier two dimensional setups. A geometric echo trick quickly moves one molecule to cancel trap drift, tripling coherence

Remarkably, the molecules were much hotter than the almost motionless ones used in rival experiments. That makes the high fidelity even more impressive

Co-authors came from Tsinghua, Imperial's Centre for Cold Matter, Korea University and USC. The work is a preprint and has not yet been peer reviewed, and the 99.9 percent figure mentioned is a projection rather than a result

Molecules have more internal states than atoms, which could make them useful for storing and processing quantum information in new ways. Getting high fidelity without extreme cooling could simplify experiments a lot. The geometric echo is a neat and practical idea

Could molecules become a serious platform for quantum computers? And how close is 97.6 percent to what is needed?

Laser-cooled Molecules Achieve Record Entanglement Despite Higher Temperaturesquantumzeitgeist.com