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arXiv · 1109.4456

Spin-guides and spin-splitters: Waveguide analogies in one-dimensional spin chains

Melissa I. Makin·Jared H. Cole·Charles D. Hill·Andrew D. Greentree
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Abstract

Here we show a direct mapping between waveguide theory and spin chain transport, opening an alternative approach to quantum information transport in the solid-state. By applying temporally varying control profiles to a spin chain, we design a virtual waveguide or 'spin-guide' to conduct individual spin excitations along defined space-time trajectories of the chain. We explicitly show that the concepts of confinement, adiabatic bend loss and beamsplitting can be mapped from optical waveguide theory to spin-guides (and hence 'spin-splitters'). Importantly, the spatial scale of applied control pulses is required to be large compared to the inter-spin spacing, and thereby allowing the design of scalable control architectures.

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Melissa I. Makin, Jared H. Cole, Charles D. Hill, Andrew D. Greentree. 2011-09-21. Spin-guides and spin-splitters: Waveguide analogies in one-dimensional spin chains. https://doi.org/10.1103/physrevlett.108.017207

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