Parametric magnon transduction to spin qubits.

The integration of heterogeneous modular units for building large-scale quantum networks requires engineering mechanisms that allow suitable transduction of quantum information. Magnon-based transducers are especially attractive due to their wide range of interactions and rich nonlinear dynamics, but most of the work to date has focused on linear magnon transduction in the traditional system composed of yttrium iron garnet and diamond, two materials with difficult integrability into wafer-scale quantum circuits. In this work, we present a different approach by using wafer-compatible materials to engineer a hybrid transducer that exploits magnon nonlinearities in a magnetic microdisc to address quantum spin defects in silicon carbide.

Wafer-scale nanofabrication of telecom single-photon emitters in silicon.

A highly promising route to scale millions of qubits is to use quantum photonic integrated circuits (PICs), where deterministic photon sources, reconfigurable optical elements, and single-photon detectors are monolithically integrated on the same silicon chip. The isolation of single-photon emitters, such as the G centers and W centers, in the optical telecommunication O-band, has recently been realized in silicon. In all previous cases, however, single-photon emitters were created uncontrollably in random locations, preventing their scalability.

Acoustically induced coherent spin trapping.

Spin centers are promising qubits for quantum technologies. Here, we show that the acoustic manipulation of spin qubits in their electronic excited state provides an approach for coherent spin control inaccessible so far. We demonstrate a giant interaction between the strain field of a surface acoustic wave (SAW) and the excited-state spin of silicon vacancies in silicon carbide, which is about two orders of magnitude stronger than in the ground state.

Engineering telecom single-photon emitters in silicon for scalable quantum photonics.

We create and isolate single-photon emitters with a high brightness approaching 10 counts per second in commercial silicon-on-insulator (SOI) wafers. The emission occurs in the infrared spectral range with a spectrally narrow zero phonon line in the telecom O-band and shows a high photostability even after days of continuous operation. The origin of the emitters is attributed to one of the carbon-related color centers in silicon, the so-called G center, allowing purification with the C and Si isotopes.