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arXiv · 1912.06173

Controlling Arbitrary Observables in Correlated Many-body Systems

Gerard McCaul·Christopher Orthodoxou·Kurt Jacobs·George H. Booth·Denys I. Bondar
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Abstract

Here we present an expanded analysis of a model for the manipulation and control of observables in a strongly correlated, many-body system, which was first presented in [McCaul et al., eprint: arXiv:1911.05006]. A field-free, non-linear equation of motion for controlling the expectation value of an essentially arbitrary observable is derived, together with rigorous constraints that determine the limits of controllability. We show that these constraints arise from the physically reasonable assumptions that the system will undergo unitary time evolution, and has enough degrees of freedom for the electrons to be mobile. Furthermore, we give examples of multiple solutions to generating target observable trajectories when the constraints are violated. Ehrenfest theorems are used to further refine the model, and provide a check on the validity of numerical simulations. Finally, the experimental feasibility of implementing the control fields generated by this model is discussed.

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Gerard McCaul, Christopher Orthodoxou, Kurt Jacobs, George H. Booth, Denys I. Bondar. 2019-12-12. Controlling Arbitrary Observables in Correlated Many-body Systems. https://doi.org/10.1103/physreva.101.053408

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