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arXiv · 2002.00237

Multidimensional dark space and its underlying symmetries: towards dissipation-protected qubits

Raul A. Santos·Fernando Iemini·Alex Kamenev·Yuval Gefen
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Abstract

Quantum systems are always subject to interactions with an environment, typically resulting in decoherence and distortion of quantum correlations. It has been recently shown that a controlled interaction with the environment may actually help to create a state, dubbed as {\em ``dark''}, which is immune to decoherence. To encode quantum information in the dark states, they need to span a space with a dimensionality larger than one, so different orthogonal states act as a computational basis. We devise a symmetry-based conceptual framework to engineer such degenerate dark spaces (DDS), protected from decoherence by the environment. We illustrate this construction with a model protocol, inspired by the fractional quantum Hall effect, where the DDS basis is isomorphic to a set of degenerate Laughlin states. The long-time steady state of our driven-dissipative model exhibits thus all the characteristics of degenerate vacua of a unitary topological system. This approach offers new possibilities for storing, protecting and manipulating quantum information in open systems.

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Raul A. Santos, Fernando Iemini, Alex Kamenev, Yuval Gefen. 2020-02-01. Multidimensional dark space and its underlying symmetries: towards dissipation-protected qubits. https://doi.org/10.1038/s41467-020-19646-4

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