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

TL;DR

This paper introduces a dissipative approach to prepare the ground state of an isotropic XY spin chain using a structured environment, enabling high-fidelity state generation without complex control techniques.

Contribution

The authors propose a novel dissipative protocol leveraging a damped harmonic oscillator as an environment to efficiently prepare the ground state of a spin chain.

Findings

Effective environment induces ground-state convergence

High fidelity in small ion chains

Protocol does not require individual addressing

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.