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arXiv · 2011.04881

Probabilistic teleportation of a quantum dot spin qubit

Y. Kojima·T. Nakajima·A. Noiri·J. Yoneda·T. Otsuka·K. Takeda·S. Li·S. D. Bartlett·A. Ludwig·A. D. Wieck·S. Tarucha
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Abstract

Electron spin s in semiconductor quantum dot s have been intensively studied for implementing quantum computation and high fidelity single and two qubit operation s have recently been achieved . Quantum teleportation is a three qubit protocol exploiting quantum entanglement and it serv es as a n essential primitive for more sophisticated quantum algorithm s Here, we demonstrate a scheme for quantum teleportation based on direct Bell measurement for a single electron spin qubit in a triple quantum dot utilizing the Pauli exclusion principle to create and detect maximally entangled state s . T he single spin polarization is teleported from the input qubit to the output qubit with a fidelity of 0.9 1 We find this fidelity is primarily limited by singlet triplet mixing which can be improved by optimizing the device parameters Our results may be extended to quantum algorithms with a larger number of se miconductor spin qubit s

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Y. Kojima, T. Nakajima, A. Noiri, J. Yoneda, T. Otsuka, K. Takeda, S. Li, S. D. Bartlett, A. Ludwig, A. D. Wieck, S. Tarucha. 2020-11-10. Probabilistic teleportation of a quantum dot spin qubit. https://doi.org/10.1038/s41534-021-00403-4

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