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arXiv · 1407.3229

Emulating quantum state transfer through a spin-1 chain on a 1D lattice of superconducting qutrits

Joydip Ghosh
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Abstract

Spin-1 systems, in comparison to spin-1/2 systems, offer a better security for encoding and transfer of quantum information, primarily due to their larger Hilbert spaces. Superconducting artificial atoms possess multiple energy-levels, thereby capable of emulating higher-spin systems. Here we consider a 1D lattice of nearest-neighbor-coupled superconducting transmon systems, and devise a scheme to transfer an arbitrary qutrit-state (a state encoded in a three-level quantum system) across the chain. We assume adjustable couplings between adjacent transmons, derive an analytic constraint for the control-pulse, and show how to satisfy the constraint to achieve a high-fidelity state-transfer under current experimental conditions. Our protocol thus enables enhanced quantum communication and information processing with promising superconducting qutrits.

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Joydip Ghosh. 2014-11-26. Emulating quantum state transfer through a spin-1 chain on a 1D lattice of superconducting qutrits. https://doi.org/10.1103/physreva.90.062318

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