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Quantum optimal control for pure-state preparation using one initial state

Günther, Stefanie·Petersson, N. Anders·DuBois, Jonathan L.
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Abstract

This paper presents a framework for solving the pure-state preparation problem using numerical optimal control. As an example, we consider the case where a number of qubits are dispersively coupled to a readout cavity. Herein, we model open system quantum dynamics using the Markovian Lindblad master equation driven by external control pulses. The main result of this paper develops a basis of density matrices (a parameterization) where each basis element is a density matrix by itself. Utilizing a specific objective function, we show how an ensemble of the basis elements can be used as a single initial state throughout the optimization process—independent of the system dimension. We apply the general framework to the specific application of ground-state reset of one and two qubits coupled to a readout cavity.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS97 MATHEMATICS AND COMPUTING

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BibTeXRIS

Günther, Stefanie, Petersson, N. Anders, DuBois, Jonathan L.. 2021-10-07. Quantum optimal control for pure-state preparation using one initial state. https://doi.org/10.1116/5.0060262

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