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arXiv · 1705.07725

Evolution-free Hamiltonian parameter estimation through Zeeman markers

Daniel Burgarth·Ashok Ajoy
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Abstract

We provide a protocol for Hamiltonian parameter estimation which relies only on the Zeeman effect. No time-dependent quantities need to be measured, it fully suffices to observe spectral shifts induced by fields applied to local `markers'. We demonstrate the idea with a simple tight-binding Hamiltonian and numerically show stability with respect to Gaussian noise on the spectral measurements. Then we generalize the result to show applicability to a wide range of systems, including quantum spin chains, networks of qubits, and coupled harmonic oscillators, and suggest potential experimental implementations.

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Daniel Burgarth, Ashok Ajoy. 2017-05-22. Evolution-free Hamiltonian parameter estimation through Zeeman markers. https://doi.org/10.1103/physrevlett.119.030402

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