Print Email Facebook Twitter Entanglement of Spin-Pair Qubits with Intrinsic Dephasing Times Exceeding a Minute Title Entanglement of Spin-Pair Qubits with Intrinsic Dephasing Times Exceeding a Minute Author Bartling, H.P. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Abobeih, M.H.M.A. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Pingault, B.J. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft; Harvard University) Degen, M.J. (TU Delft QID/Hanson Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Loenen, S.J.H. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Bradley, C.E. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Randall, J.A.D. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Markham, M. (Element Six Innovation) Twitchen, D. J. (Element Six Innovation) Taminiau, T.H. (TU Delft QID/Taminiau Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Date 2022 Abstract Understanding and protecting the coherence of individual quantum systems is a central challenge in quantum science and technology. Over the past decades, a rich variety of methods to extend coherence have been developed. A complementary approach is to look for naturally occurring systems that are inherently protected against decoherence. Here, we show that pairs of identical nuclear spins in solids form intrinsically long-lived qubits. We study three carbon-13 pairs in diamond and realize high-fidelity measurements of their quantum states using a single nitrogen-vacancy center in their vicinity. We then reveal that the spin pairs are robust to external perturbations due to a combination of three phenomena: a decoherence-free subspace, a clock transition, and a variant on motional narrowing. The resulting inhomogeneous dephasing time is T2∗=1.9(3) min, the longest reported for individually controlled qubits. Finally, we develop complete control and realize an entangled state between two spin pairs through projective parity measurements. These long-lived qubits are abundantly present in diamond and other solids and provide new opportunities for ancilla-enhanced quantum sensing and for robust memory qubits for quantum networks. To reference this document use: http://resolver.tudelft.nl/uuid:bab5b929-1c80-4556-8dbc-2da5fc2ecf33 DOI https://doi.org/10.1103/PhysRevX.12.011048 ISSN 2160-3308 Source Physical Review B, 12 (1) Part of collection Institutional Repository Document type journal article Rights © 2022 H.P. Bartling, M.H.M.A. Abobeih, B.J. Pingault, M.J. Degen, S.J.H. Loenen, C.E. Bradley, J.A.D. Randall, M. Markham, D. J. Twitchen, T.H. Taminiau Files PDF PhysRevX.12.011048.pdf 1.36 MB Close viewer /islandora/object/uuid:bab5b929-1c80-4556-8dbc-2da5fc2ecf33/datastream/OBJ/view