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Flying Spin Qubits

Vanita Srinivasa·Jeremy Levy·C. Stephen Hellberg
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Abstract

We present a method for encoding and transporting qubits within a dimerized Heisenberg spin-1/2 chain. Logical qubits are localized at the domain walls that separate the two possible dimerized states. The domain walls can be moved to produce "flying spin qubits". The topological nature of these states makes them stable against a wide class of perturbations. Pairs of domain walls can be used to generate Einstein-Podolsky-Rosen pairs of entangled qubits. We discuss speed limitations within an exactly solvable three-spin model and describe a possible physical realization using quantum dot arrays.

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Vanita Srinivasa, Jeremy Levy, C. Stephen Hellberg. 2006-12-23. Flying Spin Qubits. https://arxiv.org/abs/quant-ph/0606089

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