Long-distance excitation of nitrogen-vacancy centers in diamond via surface spin waves

Coherent communication over mesoscale distances is a necessary condition for the application of solid-state spin qubits to scalable quantum information processing. Among other routes under study, one possibility entails the use of magnetostatic surface spin waves (MSSW) coupled to shallow paramagnetic defects in wide-bandgap semiconductors. Here we present the use of room-temperature magnetostatic surface spin waves (MSSWs) propagating in yttrium iron garnet (YIG) as a medium to coherently manipulate spin in a diamond with nitrogen-vacancy (NV) centers at a distant far away from a microwave source. We demonstrated a transport spanning over 3 mm which attributed to the robustness of MSSW and the large spin-wave diffusion length of YIG[1]. With NV spins as a local sensor, we find that the MSSW couples resonantly, and the amplitude of NV spins grow linearly with the applied microwave power, suggesting that this approach could potentially be extended to amplify the signal from neighboring spin qubits by several orders of magnitude. [1] D.Kikuchi, D. Prananto, K. Hayashi, A. Laraoui, N. Mizuochi, M. Hatano, E. Saitoh, Y. Kim, C. A. Meriles, and T. An, Appl. Phys. Express 10, 103004 (2017).