Xin Zhang, Elizaveta Morozova, Maximilian Rimbach-Russ, Daniel Jirovec, Tzu-Kan Hsiao, Pablo Cova Fariña, Chien-An Wang, Stefan D. Oosterhout, Amir Sammak, Giordano Scappucci, Menno Veldhorst, Lieven M. K. Vandersypen
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引用次数: 0
Abstract
The coherent control of interacting spins in semiconductor quantum dots is of strong interest for quantum information processing and for studying quantum magnetism from the bottom up. Here we present a 2 × 4 germanium quantum dot array with full and controllable interactions between nearest-neighbour spins. As a demonstration of the level of control, we define four singlet–triplet qubits in this system and show two-axis single-qubit control of each qubit and SWAP-style two-qubit gates between all neighbouring qubit pairs, yielding average single-qubit gate fidelities of 99.49(8)–99.84(1)% and Bell state fidelities of 73(1)–90(1)%. Combining these operations, we experimentally implement a circuit designed to generate and distribute entanglement across the array. A remote Bell state with a fidelity of 75(2)% and concurrence of 22(4)% is achieved. These results highlight the potential of singlet–triplet qubits as a competing platform for quantum computing and indicate that scaling up the control of quantum dot spins in extended bilinear arrays can be feasible.
期刊介绍:
Nature Nanotechnology is a prestigious journal that publishes high-quality papers in various areas of nanoscience and nanotechnology. The journal focuses on the design, characterization, and production of structures, devices, and systems that manipulate and control materials at atomic, molecular, and macromolecular scales. It encompasses both bottom-up and top-down approaches, as well as their combinations.
Furthermore, Nature Nanotechnology fosters the exchange of ideas among researchers from diverse disciplines such as chemistry, physics, material science, biomedical research, engineering, and more. It promotes collaboration at the forefront of this multidisciplinary field. The journal covers a wide range of topics, from fundamental research in physics, chemistry, and biology, including computational work and simulations, to the development of innovative devices and technologies for various industrial sectors such as information technology, medicine, manufacturing, high-performance materials, energy, and environmental technologies. It includes coverage of organic, inorganic, and hybrid materials.