Green B L, Mottishaw S, Breeze B G, Edmonds A M, D'Haenens-Johansson U F S, Doherty M W, Williams S D, Twitchen D J, Newton M E
Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom.
Element Six Limited, Global Innovation Centre, Fermi Avenue OX11 0QR, United Kingdom.
Phys Rev Lett. 2017 Sep 1;119(9):096402. doi: 10.1103/PhysRevLett.119.096402. Epub 2017 Aug 31.
We demonstrate optical spin polarization of the neutrally charged silicon-vacancy defect in diamond (SiV^{0}), an S=1 defect which emits with a zero-phonon line at 946 nm. The spin polarization is found to be most efficient under resonant excitation, but nonzero at below-resonant energies. We measure an ensemble spin coherence time T_{2}>100 μs at low-temperature, and a spin relaxation limit of T_{1}>25 s. Optical spin-state initialization around 946 nm allows independent initialization of SiV^{0} and NV^{-} within the same optically addressed volume, and SiV^{0} emits within the telecoms down-conversion band to 1550 nm: when combined with its high Debye-Waller factor, our initial results suggest that SiV^{0} is a promising candidate for a long-range quantum communication technology.
我们展示了金刚石中中性电荷硅空位缺陷（SiV⁰）的光学自旋极化，这是一种S = 1缺陷，在946纳米处有零声子线发射。发现自旋极化在共振激发下最为有效，但在低于共振能量时也不为零。我们在低温下测量到系综自旋相干时间T₂>100 μs，自旋弛豫极限T₁>25 s。946纳米附近的光学自旋态初始化允许在同一光学寻址体积内独立初始化SiV⁰和NV⁻，并且SiV⁰在电信下转换波段发射到1550纳米：结合其高德拜-瓦勒因子，我们的初步结果表明SiV⁰是长距离量子通信技术的一个有前途的候选者。
