Trusheim Matthew E, Pingault Benjamin, Wan Noel H, Gündoğan Mustafa, De Santis Lorenzo, Debroux Romain, Gangloff Dorian, Purser Carola, Chen Kevin C, Walsh Michael, Rose Joshua J, Becker Jonas N, Lienhard Benjamin, Bersin Eric, Paradeisanos Ioannis, Wang Gang, Lyzwa Dominika, Montblanch Alejandro R-P, Malladi Girish, Bakhru Hassaram, Ferrari Andrea C, Walmsley Ian A, Atatüre Mete, Englund Dirk
Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom.
Phys Rev Lett. 2020 Jan 17;124(2):023602. doi: 10.1103/PhysRevLett.124.023602.
Solid-state quantum emitters that couple coherent optical transitions to long-lived spin qubits are essential for quantum networks. Here we report on the spin and optical properties of individual tin-vacancy (SnV) centers in diamond nanostructures. Through cryogenic magneto-optical and spin spectroscopy, we verify the inversion-symmetric electronic structure of the SnV, identify spin-conserving and spin-flipping transitions, characterize transition linewidths, measure electron spin lifetimes, and evaluate the spin dephasing time. We find that the optical transitions are consistent with the radiative lifetime limit even in nanofabricated structures. The spin lifetime is phonon limited with an exponential temperature scaling leading to T_{1}>10 ms, and the coherence time, T_{2}^{*} reaches the nuclear spin-bath limit upon cooling to 2.9 K. These spin properties exceed those of other inversion-symmetric color centers for which similar values require millikelvin temperatures. With a combination of coherent optical transitions and long spin coherence without dilution refrigeration, the SnV is a promising candidate for feasable and scalable quantum networking applications.
将相干光学跃迁与长寿命自旋量子比特相耦合的固态量子发射器对量子网络至关重要。在此，我们报告了金刚石纳米结构中单个锡空位（SnV）中心的自旋和光学性质。通过低温磁光和自旋光谱，我们验证了SnV的反演对称电子结构，识别了自旋守恒和自旋翻转跃迁，表征了跃迁线宽，测量了电子自旋寿命，并评估了自旋退相时间。我们发现，即使在纳米制造结构中，光学跃迁也与辐射寿命极限一致。自旋寿命受声子限制，具有指数温度标度，导致T1>10 ms，并且在冷却到2.9 K时，相干时间T2*达到核自旋浴场极限。这些自旋性质超过了其他反演对称色心，对于后者，类似的值需要毫开尔文温度。结合相干光学跃迁和无需稀释制冷的长自旋相干性，SnV是可行且可扩展的量子网络应用的有前途的候选者。
