Diamond Qubits Take the Stage

In the global race to build a quantum computer, it’s still unclear what material will make the best qubit. Companies have bet on a variety of architectures based on trapped ions, neutral atoms, superconducting circuits, and more. Now, Tim Taminiau of Delft University of Technology, Netherlands, and colleagues have demonstrated that they can manipulate magnetic spins inside diamond into the robust quantum states necessary for quantum computing. In their experiment, they entangle all possible pairs of a ten-qubit system and produce states in which seven different qubits are entangled simultaneously. They also show that individual qubits can retain quantum coherence for up to 75 s—a record for solid-state systems.