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arXiv · 1611.02398

Spatial non-adiabatic passage using geometric phases

Albert Benseny·Anthony Kiely·Yongping Zhang·Thomas Busch·Andreas Ruschhaupt
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Abstract

Quantum technologies based on adiabatic techniques can be highly effective, but often at the cost of being very slow. Here we introduce a set of experimentally realistic, non-adiabatic protocols for spatial state preparation, which yield the same fidelity as their adiabatic counterparts, but on fast timescales. In particular, we consider a charged particle in a system of three tunnel-coupled quantum wells, where the presence of a magnetic field can induce a geometric phase during the tunnelling processes. We show that this leads to the appearance of complex tunnelling amplitudes and allows for the implementation of spatial non-adiabatic passage. We demonstrate the ability of such a system to transport a particle between two different wells and to generate a delocalised superposition between the three traps with high fidelity in short times.

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Albert Benseny, Anthony Kiely, Yongping Zhang, Thomas Busch, Andreas Ruschhaupt. 2016-11-08. Spatial non-adiabatic passage using geometric phases. https://doi.org/10.1140/epjqt%2Fs40507-017-0056-x

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