2011/03/31 by Robert Amsüss, Christian Koller, Tobias Nöbauer +9 · 2 citations
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1103/physrevlett.107.060502
published as Phys. Rev. Lett. 107, 060502 (2011) · 5 pages, 4 figures
arxiv created 2011/08/24 · arxiv updated 2011/08/25
We report strong coupling between an ensemble of nitrogen-vacancy center electron spins in diamond and a superconducting microwave coplanar waveguide resonator. The characteristic scaling of the collective coupling strength with the square root of the number of emitters is observed directly. Additionally, we measure hyperfine coupling to 13C nuclear spins, which is a first step towards a nuclear ensemble quantum memory. Using the dispersive shift of the cavity resonance frequency, we measure the relaxation time T1 of the NV center at millikelvin temperatures in a non-destructive way.