Purcell-enhanced spin–phonon coupling with a single colour centre
Researchers have successfully observed the acoustic Purcell effect by engineering a microwave-frequency nanomechanical resonator around a colour-centre spin qubit in diamond. This study demonstrates that placing an electromagnetic resonator around emitters can enhance spontaneous emission, a concept originally proposed by Purcell in the 1940s for photons, now applied to phonons in solid-state systems. By utilizing a co-localized optical mode that strongly couples to the excited state of the colour centre, the team performed single-photon-level laser spectroscopy at millikelvin temperatures. They recorded a ten-fold increase in spin relaxation speed when the spin qubit was tuned into resonance with a 12 GHz acoustic mode. Furthermore, the colour centre served as an atomic-scale probe to measure the broadband phonon spectrum of the nanostructure up to 28 GHz. This breakthrough establishes a new regime for controlling quantum defects in solids, potentially enabling interconnects between atomic-scale quantum memories and qubits encoded in acoustic and superconducting devices, thereby advancing quantum computing and communication technologies.
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Purcell-enhanced spin–phonon coupling with a single colour centre
Researchers have successfully observed the acoustic Purcell effect by engineering a microwave-frequency nanomechanical resonator around a colour-centre spin qubit in diamond. This study demonstrates that placing an electromagnetic resonator around emitters can enhance spontaneous emission, a concept originally proposed by Purcell in the 1940s for photons, now applied to phonons in solid-state systems. By utilizing a co-localized optical mode that strongly couples to the excited state of the colour centre, the team performed single-photon-level laser spectroscopy at millikelvin temperatures. They recorded a ten-fold increase in spin relaxation speed when the spin qubit was tuned into resonance with a 12 GHz acoustic mode. Furthermore, the colour centre served as an atomic-scale probe to measure the broadband phonon spectrum of the nanostructure up to 28 GHz. This breakthrough establishes a new regime for controlling quantum defects in solids, potentially enabling interconnects between atomic-scale quantum memories and qubits encoded in acoustic and superconducting devices, thereby advancing quantum computing and communication technologies.
Nature