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arXiv · 1907.00841

Local-in-time error in variational quantum dynamics

Rocco Martinazzo·Irene Burghardt
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Abstract

The McLachlan "minimum-distance" principle for optimizing approximate solutions of the time-dependent Schrodinger equation is revisited, with a focus on the local-in-time error accompanying the variational solutions. Simple, exact expressions are provided for this error, which are then evaluated in illustrative cases, notably the widely used mean-field approach and the adiabatic quantum molecular dynamics. These findings pave the way for the rigorous development of adaptive schemes that re-size on-the-fly the underlying variational manifold and thus optimize the overall computational cost of a quantum dynamical simulation.

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Rocco Martinazzo, Irene Burghardt. 2019-07-01. Local-in-time error in variational quantum dynamics. https://doi.org/10.1103/physrevlett.124.150601

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