Vanadium spin qubits as telecom quantum emitters in silicon carbide

Solid state quantum emitters with addressable spin registers are promising platforms for quantum communication, yet few emit in the telecom band necessary for low-loss fiber networks. Here we create and isolate single vanadium dopants in silicon carbide (SiC) with emission in the O-band (~1300 nm) and with brightness allowing cavity-free detection, in a wafer scale CMOS-compatible material [1]. We demonstrate that their emission is stable and narrow near surfaces, enabling integration with nanoscale devices.

We characterize the complex d¹ orbital physics in vanadium ensembles in all five sites available in 4H- and 6H-SiC. The optical transitions are observed to be sensitive to mass shifts from the distribution of nearest neighbor silicon and carbon isotopes, enabling optically resolved nuclear spin registers. Optically detected magnetic resonance of ground and excited states’ spin transitions reveal diverse hyperfine interactions with the vanadium nuclear spin and offer clock transitions for use as quantum memories. Finally, we demonstrate coherent quantum control of the spin state at 3.3 K. These results provide a path for solid-state telecom emitters for quantum applications.

[1] G. Wolfowicz, et al., Science Advances 6 (18), eaaz1192 (2020)