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arXiv · 1904.05694

Spin entangled state transfer in quantum dot arrays: Coherent adiabatic and speed-up protocols

Yue Ban·Xi Chen·Sigmund Kohler·Gloria Platero
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Abstract

Long-distance transfer of quantum states is an indispensable part of large-scale quantum information processing. We propose a novel scheme for the transfer of two-electron entangled states, from one edge of a quantum dot array to the other by coherent adiabatic passage. This protocol is mediated by pulsed tunneling barriers. In a second step, we seek for a speed up by shortcut to adiabaticity techniques. This significantly reduces the operation time and, thus, minimizes the impact of decoherence. For typical parameters of state-of-the-art solid state devices, the accelerated protocol has an operation time in the nanosecond range and terminates before a major coherence loss sets in. The scheme represents a promising candidate for entanglement transfer in solid state quantum information processing.

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Yue Ban, Xi Chen, Sigmund Kohler, Gloria Platero. 2019-04-11. Spin entangled state transfer in quantum dot arrays: Coherent adiabatic and speed-up protocols. https://doi.org/10.1002/qute.201900048

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