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arXiv · 0810.2866

Coupling strength estimation for spin chains despite restricted access

Daniel Burgarth·Koji Maruyama·Franco Nori
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Abstract

Quantum control requires full knowledge of the system many-body Hamiltonian. In many cases this information is not directly available due to restricted access to the system. Here we show how to indirectly estimate all the coupling strengths in a spin chain by measuring one spin at the end of the chain. We also discuss the efficiency of this "quantum inverse problem" and give a numerical example.

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Daniel Burgarth, Koji Maruyama, Franco Nori. 2008-12-19. Coupling strength estimation for spin chains despite restricted access. https://doi.org/10.1103/physreva.79.020305

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