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arXiv · 1304.2201

Dissipative ground-state preparation of a spin chain by a structured environment

Cecilia Cormick·Alejandro Bermudez·Susana F. Huelga·Martin B. Plenio
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Abstract

We propose a dissipative method to prepare the ground state of the isotropic XY spin Hamiltonian in a transverse field. Our model consists of a spin chain with nearest-neighbour interactions and an additional collective coupling of the spins to a damped harmonic oscillator. The latter provides an effective environment with a Lorentzian spectral density and can be used to drive the chain asymptotically towards its multipartite-entangled ground state at a rate that depends on the degree of non-Markovianity of the evolution. We also present a detailed proposal for the experimental implementation with a chain of trapped ions. The protocol does not require individual addressing, concatenated pulses, or multi-particle jump operators, and is capable of generating the desired target state in small ion chains with very high fidelities.

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Cecilia Cormick, Alejandro Bermudez, Susana F. Huelga, Martin B. Plenio. 2013-07-16. Dissipative ground-state preparation of a spin chain by a structured environment. https://doi.org/10.1088/1367-2630%2F15%2F7%2F073027

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