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arXiv · 1510.05221

Electrical Control of Strong Spin-Phonon Coupling in a Carbon Nanotube

Fang-Yu Hong·Jing-Li Fu·Yan Wu·Zhi-Yan Zhu
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Abstract

We describe an approach to electrically control the strong interaction between a single electron spin and the vibrational motion of a suspended carbon nanotube resonator. The strength of the deflection-induced spin-phonon coupling is dependent on the wavefunction of the electron confined in a lateral carbon nanotube quantum dot. An electrical field along the nanotube shifts the effective center of the quantum dot, leading to the corresponding modification of the spin-phonon strength. Numerical simulations with experimentally reachable parameters show that high fidelity quantum state transfer between mechanical and spin qubits driven by electrical pulses is feasible. Our results form the basis for the fully electrical control of the coherent interconvertion between light and spin qubits and for manufacturing electrically driven quantum information processing systems.

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Fang-Yu Hong, Jing-Li Fu, Yan Wu, Zhi-Yan Zhu. 2015-10-18. Electrical Control of Strong Spin-Phonon Coupling in a Carbon Nanotube. https://arxiv.org/abs/1510.05221

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